The DOI matches its Crossref record; 43 of the 45 references it cites were found in a registry or an index; none of the 23 sources its claims cite is checked for support yet.
Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate
Open accessAbstract
Objective To use aromatase inhibition for induction of ovulation in women in whom clomiphene citrate (CC) treatment was unsuccessful. Design Prospective trial in infertility patients treated with CC. Setting Two tertiary-referral infertility clinics associated with the Division of Reproductive Sciences, University of Toronto. Patient(s) Twelve patients with anovulatory polycystic ovary syndrome (PCOS) and 10 patients with ovulatory infertility, all of whom had previously received CC with an inadequate outcome (no ovulation and/or endometrial thickness of Intervention(s) The aromatase inhibitor letrozole was given orally in a dose of 2.5 mg on days 3-7 after menses. Main outcome measure(s) Occurrence of ovulation, endometrial thickness, and pregnancy rates. Result(s) With CC treatment in patients with PCOS, ovulation occurred in 8 of 18 cycles (44.4%), and all ovulatory cycles for the women included in this study had endometrial thickness of Conclusion(s) Oral administration of the aromatase inhibitor letrozole is effective for ovulation induction in anovulatory infertility and for increased follicle recruitment in ovulatory infertility. Letrozole appears to avoid the unfavorable effects on the endometrium frequently seen with antiestrogen use for ovulation induction.
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A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In ovulatory patients, the serum E 2 level was 719 pmol/L in letrozole treatment cycles versus 3,003 pmol/L in CC treatment cycles.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > RESULTS
plainn = 10- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
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A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In the 10 patients with ovulatory infertility, letrozole treatment resulted in a mean number of 2.3 mature follicles and mean endometrial thickness of 0.8 cm.”
- Also stated in: § RESULTS · plain
“The mean number of follicles measuring Ͼ1.5 cm on the day of hCG administration was 2.3 (range, 1-4).”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > Abstract Objective: To use aromatase inhibition for induction of ovulation in women in whom clomiphene citrate (CC) treatment was unsuccessful.Design: Prospective trial in infertility patients treated with CC.Setting: Two tertiary-referral infertility clinics associated with the Division of Reproductive Sciences, University of Toronto.Patient(s): Twelve patients with anovulatory polycystic ovary syndrome (PCOS) and 10 patients with ovulatory infertility, all of whom had previously received CC with an inadequate outcome (no ovulation and/or endometrial thickness of Յ0.5 cm).Intervention(s): The aromatase inhibitor letrozole was given orally in a dose of 2.5 mg on days 3-7 after menses.Main Outcome Measure(s): Occurrence of ovulation, endometrial thickness, and pregnancy rates.Result(s): With CC treatment in patients with PCOS, ovulation occurred in 8 of 18 cycles (44.4%), and all ovulatory cycles for the women included in this study had endometrial thickness of Յ0.5 cm.In 10 ovulatory patients, 15 CC cycles resulted in a mean number of 2.5 mature follicles, but all cycles had endometrial thickness of Յ0.5 cm on the day of hCG administration.With letrozole treatment in the same patients with PCOS, ovulation occurred in 9 of 12 cycles (75%) and pregnancy was achieved in 3 patients (25%).In the 10 patients with ovulatory infertility, letrozole treatment resulted in a mean number of 2.3 mature follicles and mean endometrial thickness of 0.8 cm.Pregnancy was achieved in 1 patient (10%).Conclusion(s): Oral administration of the aromatase inhibitor letrozole is effective for ovulation induction in anovulatory infertility and for increased follicle recruitment in ovulatory infertility.Letrozole appears to avoid the unfavorable effects on the endometrium frequently seen with antiestrogen use for ovulation induction.(Fertil Steril 2001;75:305-9.©2001 by American Society for Reproductive Medicine.) In women with World Health Organization type II anovulatory infertility, the treatment of first choice for the induction of ovulation is an antiestrogen, most commonly clomiphene citrate (CC) (1,2).However, 20%-25% of women are resistant to CC and do not ovulate.In addition, clinical data have revealed a discrepancy between ovulation and conception rates during CC treatment and a higher than expected incidence of miscarriage in conception cycles (3)(4)(5)(6).These observations have been attributed to the antiestrogenic mechanism of action of CC, which involves long-lasting estrogen receptor (ER) depletion.It also appears that CC accumulates in the body because of its long half-life (7).As a result, CC may have a negative effect on the quality and quantity of cervical mucus (8), on endometrial development (9), and on other as yet undetermined fertility factors (10,11). After failure of CC, gonadotropin preparations such as hMG or pure FSH have been used as a second-line treatment for ovulation induction.In women with polycystic ovary syndrome (PCOS), because of the high sensitivity of the ovaries to gonadotropin stimulation, treatment with hMG or pure FSH is difficult to control and characteristically induces several ovulatory follicles, leading to the risk of multiple pregnancies and ovarian hyperstimulation syndrome (OHSS) (12).Therefore, a simple oral treatment that could be used without risk of hyperstimulation and with minimal monitoring would be the preferred therapy.
plaindirectn = 10- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Also stated in: § RESULTS · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“On the day of hCG administration in patients with PCOS, the mean serum E 2 concentration was 962 pmol/L in letrozole treatment cycles, versus 1,638 pmol/L in CC treatment cycles.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > RESULTS
plainn = 10- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In the 10 patients with ovulatory infertility, letrozole treatment resulted in a mean number of 2.3 mature follicles and mean endometrial thickness of 0.8 cm.”
- Also stated in: § RESULTS · plain
“Mean endometrial thicknesses on the day of hCG administration in patients with PCOS and ovulatory patients was 0.81 and 0.89 cm with letrozole, compared with 0.62 and 0.52 cm in CC treatment cycles, respectively.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > Abstract Objective: To use aromatase inhibition for induction of ovulation in women in whom clomiphene citrate (CC) treatment was unsuccessful.Design: Prospective trial in infertility patients treated with CC.Setting: Two tertiary-referral infertility clinics associated with the Division of Reproductive Sciences, University of Toronto.Patient(s): Twelve patients with anovulatory polycystic ovary syndrome (PCOS) and 10 patients with ovulatory infertility, all of whom had previously received CC with an inadequate outcome (no ovulation and/or endometrial thickness of Յ0.5 cm).Intervention(s): The aromatase inhibitor letrozole was given orally in a dose of 2.5 mg on days 3-7 after menses.Main Outcome Measure(s): Occurrence of ovulation, endometrial thickness, and pregnancy rates.Result(s): With CC treatment in patients with PCOS, ovulation occurred in 8 of 18 cycles (44.4%), and all ovulatory cycles for the women included in this study had endometrial thickness of Յ0.5 cm.In 10 ovulatory patients, 15 CC cycles resulted in a mean number of 2.5 mature follicles, but all cycles had endometrial thickness of Յ0.5 cm on the day of hCG administration.With letrozole treatment in the same patients with PCOS, ovulation occurred in 9 of 12 cycles (75%) and pregnancy was achieved in 3 patients (25%).In the 10 patients with ovulatory infertility, letrozole treatment resulted in a mean number of 2.3 mature follicles and mean endometrial thickness of 0.8 cm.Pregnancy was achieved in 1 patient (10%).Conclusion(s): Oral administration of the aromatase inhibitor letrozole is effective for ovulation induction in anovulatory infertility and for increased follicle recruitment in ovulatory infertility.Letrozole appears to avoid the unfavorable effects on the endometrium frequently seen with antiestrogen use for ovulation induction.(Fertil Steril 2001;75:305-9.©2001 by American Society for Reproductive Medicine.) In women with World Health Organization type II anovulatory infertility, the treatment of first choice for the induction of ovulation is an antiestrogen, most commonly clomiphene citrate (CC) (1,2).However, 20%-25% of women are resistant to CC and do not ovulate.In addition, clinical data have revealed a discrepancy between ovulation and conception rates during CC treatment and a higher than expected incidence of miscarriage in conception cycles (3)(4)(5)(6).These observations have been attributed to the antiestrogenic mechanism of action of CC, which involves long-lasting estrogen receptor (ER) depletion.It also appears that CC accumulates in the body because of its long half-life (7).As a result, CC may have a negative effect on the quality and quantity of cervical mucus (8), on endometrial development (9), and on other as yet undetermined fertility factors (10,11). After failure of CC, gonadotropin preparations such as hMG or pure FSH have been used as a second-line treatment for ovulation induction.In women with polycystic ovary syndrome (PCOS), because of the high sensitivity of the ovaries to gonadotropin stimulation, treatment with hMG or pure FSH is difficult to control and characteristically induces several ovulatory follicles, leading to the risk of multiple pregnancies and ovarian hyperstimulation syndrome (OHSS) (12).Therefore, a simple oral treatment that could be used without risk of hyperstimulation and with minimal monitoring would be the preferred therapy.
plaindirectn = 10- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Also stated in: § RESULTS · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“No pregnancy was achieved in any of the ovulatory cycles.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > RESULTS
plainn = 12- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“With letrozole treatment in the same patients with PCOS, ovulation occurred in 9 of 12 cycles (75%) and pregnancy was achieved in 3 patients (25%).”
- Also stated in: § RESULTS · plain
“Pregnancy was achieved in 3 cycles (25%), 2 of which were singleton clinical pregnancies and 1 of which was a chemical pregnancy.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > Abstract Objective: To use aromatase inhibition for induction of ovulation in women in whom clomiphene citrate (CC) treatment was unsuccessful.Design: Prospective trial in infertility patients treated with CC.Setting: Two tertiary-referral infertility clinics associated with the Division of Reproductive Sciences, University of Toronto.Patient(s): Twelve patients with anovulatory polycystic ovary syndrome (PCOS) and 10 patients with ovulatory infertility, all of whom had previously received CC with an inadequate outcome (no ovulation and/or endometrial thickness of Յ0.5 cm).Intervention(s): The aromatase inhibitor letrozole was given orally in a dose of 2.5 mg on days 3-7 after menses.Main Outcome Measure(s): Occurrence of ovulation, endometrial thickness, and pregnancy rates.Result(s): With CC treatment in patients with PCOS, ovulation occurred in 8 of 18 cycles (44.4%), and all ovulatory cycles for the women included in this study had endometrial thickness of Յ0.5 cm.In 10 ovulatory patients, 15 CC cycles resulted in a mean number of 2.5 mature follicles, but all cycles had endometrial thickness of Յ0.5 cm on the day of hCG administration.With letrozole treatment in the same patients with PCOS, ovulation occurred in 9 of 12 cycles (75%) and pregnancy was achieved in 3 patients (25%).In the 10 patients with ovulatory infertility, letrozole treatment resulted in a mean number of 2.3 mature follicles and mean endometrial thickness of 0.8 cm.Pregnancy was achieved in 1 patient (10%).Conclusion(s): Oral administration of the aromatase inhibitor letrozole is effective for ovulation induction in anovulatory infertility and for increased follicle recruitment in ovulatory infertility.Letrozole appears to avoid the unfavorable effects on the endometrium frequently seen with antiestrogen use for ovulation induction.(Fertil Steril 2001;75:305-9.©2001 by American Society for Reproductive Medicine.) In women with World Health Organization type II anovulatory infertility, the treatment of first choice for the induction of ovulation is an antiestrogen, most commonly clomiphene citrate (CC) (1,2).However, 20%-25% of women are resistant to CC and do not ovulate.In addition, clinical data have revealed a discrepancy between ovulation and conception rates during CC treatment and a higher than expected incidence of miscarriage in conception cycles (3)(4)(5)(6).These observations have been attributed to the antiestrogenic mechanism of action of CC, which involves long-lasting estrogen receptor (ER) depletion.It also appears that CC accumulates in the body because of its long half-life (7).As a result, CC may have a negative effect on the quality and quantity of cervical mucus (8), on endometrial development (9), and on other as yet undetermined fertility factors (10,11). After failure of CC, gonadotropin preparations such as hMG or pure FSH have been used as a second-line treatment for ovulation induction.In women with polycystic ovary syndrome (PCOS), because of the high sensitivity of the ovaries to gonadotropin stimulation, treatment with hMG or pure FSH is difficult to control and characteristically induces several ovulatory follicles, leading to the risk of multiple pregnancies and ovarian hyperstimulation syndrome (OHSS) (12).Therefore, a simple oral treatment that could be used without risk of hyperstimulation and with minimal monitoring would be the preferred therapy.
plaindirectn = 3- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Also stated in: § RESULTS · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Mean endometrial thicknesses on the day of hCG administration in patients with PCOS and ovulatory patients was 0.81 and 0.89 cm with letrozole, compared with 0.62 and 0.52 cm in CC treatment cycles, respectively.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > RESULTS
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Pregnancy was achieved in 1 patient (10%).”
- Also stated in: § RESULTS · plain
“A singleton clinical pregnancy (10%) resulted from timed intrauterine insemination in one couple with unexplained infertility who developed 2 follicles of Ͼ1.5 cm.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > Abstract Objective: To use aromatase inhibition for induction of ovulation in women in whom clomiphene citrate (CC) treatment was unsuccessful.Design: Prospective trial in infertility patients treated with CC.Setting: Two tertiary-referral infertility clinics associated with the Division of Reproductive Sciences, University of Toronto.Patient(s): Twelve patients with anovulatory polycystic ovary syndrome (PCOS) and 10 patients with ovulatory infertility, all of whom had previously received CC with an inadequate outcome (no ovulation and/or endometrial thickness of Յ0.5 cm).Intervention(s): The aromatase inhibitor letrozole was given orally in a dose of 2.5 mg on days 3-7 after menses.Main Outcome Measure(s): Occurrence of ovulation, endometrial thickness, and pregnancy rates.Result(s): With CC treatment in patients with PCOS, ovulation occurred in 8 of 18 cycles (44.4%), and all ovulatory cycles for the women included in this study had endometrial thickness of Յ0.5 cm.In 10 ovulatory patients, 15 CC cycles resulted in a mean number of 2.5 mature follicles, but all cycles had endometrial thickness of Յ0.5 cm on the day of hCG administration.With letrozole treatment in the same patients with PCOS, ovulation occurred in 9 of 12 cycles (75%) and pregnancy was achieved in 3 patients (25%).In the 10 patients with ovulatory infertility, letrozole treatment resulted in a mean number of 2.3 mature follicles and mean endometrial thickness of 0.8 cm.Pregnancy was achieved in 1 patient (10%).Conclusion(s): Oral administration of the aromatase inhibitor letrozole is effective for ovulation induction in anovulatory infertility and for increased follicle recruitment in ovulatory infertility.Letrozole appears to avoid the unfavorable effects on the endometrium frequently seen with antiestrogen use for ovulation induction.(Fertil Steril 2001;75:305-9.©2001 by American Society for Reproductive Medicine.) In women with World Health Organization type II anovulatory infertility, the treatment of first choice for the induction of ovulation is an antiestrogen, most commonly clomiphene citrate (CC) (1,2).However, 20%-25% of women are resistant to CC and do not ovulate.In addition, clinical data have revealed a discrepancy between ovulation and conception rates during CC treatment and a higher than expected incidence of miscarriage in conception cycles (3)(4)(5)(6).These observations have been attributed to the antiestrogenic mechanism of action of CC, which involves long-lasting estrogen receptor (ER) depletion.It also appears that CC accumulates in the body because of its long half-life (7).As a result, CC may have a negative effect on the quality and quantity of cervical mucus (8), on endometrial development (9), and on other as yet undetermined fertility factors (10,11). After failure of CC, gonadotropin preparations such as hMG or pure FSH have been used as a second-line treatment for ovulation induction.In women with polycystic ovary syndrome (PCOS), because of the high sensitivity of the ovaries to gonadotropin stimulation, treatment with hMG or pure FSH is difficult to control and characteristically induces several ovulatory follicles, leading to the risk of multiple pregnancies and ovarian hyperstimulation syndrome (OHSS) (12).Therefore, a simple oral treatment that could be used without risk of hyperstimulation and with minimal monitoring would be the preferred therapy.
plaindirectSingle case- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Also stated in: § RESULTS · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In 10 ovulatory patients, 15 CC cycles resulted in a mean number of 2.5 mature follicles, but all cycles had endometrial thickness of Յ0.5 cm on the day of hCG administration.”
- Also stated in: § RESULTS · plain
“The mean number of follicles measuring Ͼ1.5 cm on the day of hCG administration was 2.5 follicles (range, 1-5).”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > Abstract Objective: To use aromatase inhibition for induction of ovulation in women in whom clomiphene citrate (CC) treatment was unsuccessful.Design: Prospective trial in infertility patients treated with CC.Setting: Two tertiary-referral infertility clinics associated with the Division of Reproductive Sciences, University of Toronto.Patient(s): Twelve patients with anovulatory polycystic ovary syndrome (PCOS) and 10 patients with ovulatory infertility, all of whom had previously received CC with an inadequate outcome (no ovulation and/or endometrial thickness of Յ0.5 cm).Intervention(s): The aromatase inhibitor letrozole was given orally in a dose of 2.5 mg on days 3-7 after menses.Main Outcome Measure(s): Occurrence of ovulation, endometrial thickness, and pregnancy rates.Result(s): With CC treatment in patients with PCOS, ovulation occurred in 8 of 18 cycles (44.4%), and all ovulatory cycles for the women included in this study had endometrial thickness of Յ0.5 cm.In 10 ovulatory patients, 15 CC cycles resulted in a mean number of 2.5 mature follicles, but all cycles had endometrial thickness of Յ0.5 cm on the day of hCG administration.With letrozole treatment in the same patients with PCOS, ovulation occurred in 9 of 12 cycles (75%) and pregnancy was achieved in 3 patients (25%).In the 10 patients with ovulatory infertility, letrozole treatment resulted in a mean number of 2.3 mature follicles and mean endometrial thickness of 0.8 cm.Pregnancy was achieved in 1 patient (10%).Conclusion(s): Oral administration of the aromatase inhibitor letrozole is effective for ovulation induction in anovulatory infertility and for increased follicle recruitment in ovulatory infertility.Letrozole appears to avoid the unfavorable effects on the endometrium frequently seen with antiestrogen use for ovulation induction.(Fertil Steril 2001;75:305-9.©2001 by American Society for Reproductive Medicine.) In women with World Health Organization type II anovulatory infertility, the treatment of first choice for the induction of ovulation is an antiestrogen, most commonly clomiphene citrate (CC) (1,2).However, 20%-25% of women are resistant to CC and do not ovulate.In addition, clinical data have revealed a discrepancy between ovulation and conception rates during CC treatment and a higher than expected incidence of miscarriage in conception cycles (3)(4)(5)(6).These observations have been attributed to the antiestrogenic mechanism of action of CC, which involves long-lasting estrogen receptor (ER) depletion.It also appears that CC accumulates in the body because of its long half-life (7).As a result, CC may have a negative effect on the quality and quantity of cervical mucus (8), on endometrial development (9), and on other as yet undetermined fertility factors (10,11). After failure of CC, gonadotropin preparations such as hMG or pure FSH have been used as a second-line treatment for ovulation induction.In women with polycystic ovary syndrome (PCOS), because of the high sensitivity of the ovaries to gonadotropin stimulation, treatment with hMG or pure FSH is difficult to control and characteristically induces several ovulatory follicles, leading to the risk of multiple pregnancies and ovarian hyperstimulation syndrome (OHSS) (12).Therefore, a simple oral treatment that could be used without risk of hyperstimulation and with minimal monitoring would be the preferred therapy.
plaindirectn = 10- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Also stated in: § RESULTS · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Ovulation occurred in 8 cycles (44.4%) with an endometrial thickness of Յ0.5 cm.”
- Also stated in: § Abstract Objective: To use aromatase inhibition for induction of ovulation in women in whom clomiphene citrate (CC) treatment was unsuccessful.Design: Prospective trial in infertility patients treated with CC.Setting: Two tertiary-referral infertility clinics associated with the Division of Reproductive Sciences, University of Toronto.Patient(s): Twelve patients with anovulatory polycystic ovary syndrome (PCOS) and 10 patients with ovulatory infertility, all of whom had previously received CC with an inadequate outcome (no ovulation and/or endometrial thickness of Յ0.5 cm).Intervention(s): The aromatase inhibitor letrozole was given orally in a dose of 2.5 mg on days 3-7 after menses.Main Outcome Measure(s): Occurrence of ovulation, endometrial thickness, and pregnancy rates.Result(s): With CC treatment in patients with PCOS, ovulation occurred in 8 of 18 cycles (44.4%), and all ovulatory cycles for the women included in this study had endometrial thickness of Յ0.5 cm.In 10 ovulatory patients, 15 CC cycles resulted in a mean number of 2.5 mature follicles, but all cycles had endometrial thickness of Յ0.5 cm on the day of hCG administration.With letrozole treatment in the same patients with PCOS, ovulation occurred in 9 of 12 cycles (75%) and pregnancy was achieved in 3 patients (25%).In the 10 patients with ovulatory infertility, letrozole treatment resulted in a mean number of 2.3 mature follicles and mean endometrial thickness of 0.8 cm.Pregnancy was achieved in 1 patient (10%).Conclusion(s): Oral administration of the aromatase inhibitor letrozole is effective for ovulation induction in anovulatory infertility and for increased follicle recruitment in ovulatory infertility.Letrozole appears to avoid the unfavorable effects on the endometrium frequently seen with antiestrogen use for ovulation induction.(Fertil Steril 2001;75:305-9.©2001 by American Society for Reproductive Medicine.) In women with World Health Organization type II anovulatory infertility, the treatment of first choice for the induction of ovulation is an antiestrogen, most commonly clomiphene citrate (CC) (1,2).However, 20%-25% of women are resistant to CC and do not ovulate.In addition, clinical data have revealed a discrepancy between ovulation and conception rates during CC treatment and a higher than expected incidence of miscarriage in conception cycles (3)(4)(5)(6).These observations have been attributed to the antiestrogenic mechanism of action of CC, which involves long-lasting estrogen receptor (ER) depletion.It also appears that CC accumulates in the body because of its long half-life (7).As a result, CC may have a negative effect on the quality and quantity of cervical mucus (8), on endometrial development (9), and on other as yet undetermined fertility factors (10,11). After failure of CC, gonadotropin preparations such as hMG or pure FSH have been used as a second-line treatment for ovulation induction.In women with polycystic ovary syndrome (PCOS), because of the high sensitivity of the ovaries to gonadotropin stimulation, treatment with hMG or pure FSH is difficult to control and characteristically induces several ovulatory follicles, leading to the risk of multiple pregnancies and ovarian hyperstimulation syndrome (OHSS) (12).Therefore, a simple oral treatment that could be used without risk of hyperstimulation and with minimal monitoring would be the preferred therapy. · plain
“With CC treatment in patients with PCOS, ovulation occurred in 8 of 18 cycles (44.4%), and all ovulatory cycles for the women included in this study had endometrial thickness of Յ0.5 cm.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > RESULTS
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Also stated in: § Abstract Objective: To use aromatase inhibition for induction of ovulation in women in whom clomiphene citrate (CC) treatment was unsuccessful.Design: Prospective trial in infertility patients treated with CC.Setting: Two tertiary-referral infertility clinics associated with the Division of Reproductive Sciences, University of Toronto.Patient(s): Twelve patients with anovulatory polycystic ovary syndrome (PCOS) and 10 patients with ovulatory infertility, all of whom had previously received CC with an inadequate outcome (no ovulation and/or endometrial thickness of Յ0.5 cm).Intervention(s): The aromatase inhibitor letrozole was given orally in a dose of 2.5 mg on days 3-7 after menses.Main Outcome Measure(s): Occurrence of ovulation, endometrial thickness, and pregnancy rates.Result(s): With CC treatment in patients with PCOS, ovulation occurred in 8 of 18 cycles (44.4%), and all ovulatory cycles for the women included in this study had endometrial thickness of Յ0.5 cm.In 10 ovulatory patients, 15 CC cycles resulted in a mean number of 2.5 mature follicles, but all cycles had endometrial thickness of Յ0.5 cm on the day of hCG administration.With letrozole treatment in the same patients with PCOS, ovulation occurred in 9 of 12 cycles (75%) and pregnancy was achieved in 3 patients (25%).In the 10 patients with ovulatory infertility, letrozole treatment resulted in a mean number of 2.3 mature follicles and mean endometrial thickness of 0.8 cm.Pregnancy was achieved in 1 patient (10%).Conclusion(s): Oral administration of the aromatase inhibitor letrozole is effective for ovulation induction in anovulatory infertility and for increased follicle recruitment in ovulatory infertility.Letrozole appears to avoid the unfavorable effects on the endometrium frequently seen with antiestrogen use for ovulation induction.(Fertil Steril 2001;75:305-9.©2001 by American Society for Reproductive Medicine.) In women with World Health Organization type II anovulatory infertility, the treatment of first choice for the induction of ovulation is an antiestrogen, most commonly clomiphene citrate (CC) (1,2).However, 20%-25% of women are resistant to CC and do not ovulate.In addition, clinical data have revealed a discrepancy between ovulation and conception rates during CC treatment and a higher than expected incidence of miscarriage in conception cycles (3)(4)(5)(6).These observations have been attributed to the antiestrogenic mechanism of action of CC, which involves long-lasting estrogen receptor (ER) depletion.It also appears that CC accumulates in the body because of its long half-life (7).As a result, CC may have a negative effect on the quality and quantity of cervical mucus (8), on endometrial development (9), and on other as yet undetermined fertility factors (10,11). After failure of CC, gonadotropin preparations such as hMG or pure FSH have been used as a second-line treatment for ovulation induction.In women with polycystic ovary syndrome (PCOS), because of the high sensitivity of the ovaries to gonadotropin stimulation, treatment with hMG or pure FSH is difficult to control and characteristically induces several ovulatory follicles, leading to the risk of multiple pregnancies and ovarian hyperstimulation syndrome (OHSS) (12).Therefore, a simple oral treatment that could be used without risk of hyperstimulation and with minimal monitoring would be the preferred therapy. · plain
- It may state two separate claims as one. 10
- The quote only partly states this claim. 1
- Probably not a substantial claim. 8
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“At the time of writing, the three clinical pregnancies had resulted in a normal live birth and two ongoing singleton pregnancies.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > RESULTS
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
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It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“However, the endometrial thickness was Յ0.5 cm in all cycles, and no pregnancy was achieved.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > RESULTS
plainn = 10- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
The quote only partly states this claim.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Compared with CC, letrozole produced a significantly thicker endometrium on the day of hCG administration despite the significantly lower E 2 levels in both patients with PCOS and the ovulatory patients.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > FERTILITY & STERILITY
plaindirect- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Aromatase inhibitors have potential as alternatives to, or even replacements for, CC as a first-line treatment for ovulation induction in anovulatory infertility and for augmentation of ovulation in ovulatory infertility patients.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > FERTILITY & STERILITY
hedgedconditionaln = 10- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
In the paper
“Recent data support a stimulatory role for androgens in early follicular growth in primates, in contrast to the inhibitory effect observed in rodents (21).”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > FERTILITY & STERILITY
What the sources say
- Not checked — no full text of the sourcecites [21] Weil, 1998, Androgen receptor gene expression in the primate ovary, J Clin Endocrinol Metab source
plaindirect- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
In the paper
“In women with polycystic ovary syndrome (PCOS), because of the high sensitivity of the ovaries to gonadotropin stimulation, treatment with hMG or pure FSH is difficult to control and characteristically induces several ovulatory follicles, leading to the risk of multiple pregnancies and ovarian hyperstimulation syndrome (OHSS) (12).”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > Abstract Objective: To use aromatase inhibition for induction of ovulation in women in whom clomiphene citrate (CC) treatment was unsuccessful.Design: Prospective trial in infertility patients treated with CC.Setting: Two tertiary-referral infertility clinics associated with the Division of Reproductive Sciences, University of Toronto.Patient(s): Twelve patients with anovulatory polycystic ovary syndrome (PCOS) and 10 patients with ovulatory infertility, all of whom had previously received CC with an inadequate outcome (no ovulation and/or endometrial thickness of Յ0.5 cm).Intervention(s): The aromatase inhibitor letrozole was given orally in a dose of 2.5 mg on days 3-7 after menses.Main Outcome Measure(s): Occurrence of ovulation, endometrial thickness, and pregnancy rates.Result(s): With CC treatment in patients with PCOS, ovulation occurred in 8 of 18 cycles (44.4%), and all ovulatory cycles for the women included in this study had endometrial thickness of Յ0.5 cm.In 10 ovulatory patients, 15 CC cycles resulted in a mean number of 2.5 mature follicles, but all cycles had endometrial thickness of Յ0.5 cm on the day of hCG administration.With letrozole treatment in the same patients with PCOS, ovulation occurred in 9 of 12 cycles (75%) and pregnancy was achieved in 3 patients (25%).In the 10 patients with ovulatory infertility, letrozole treatment resulted in a mean number of 2.3 mature follicles and mean endometrial thickness of 0.8 cm.Pregnancy was achieved in 1 patient (10%).Conclusion(s): Oral administration of the aromatase inhibitor letrozole is effective for ovulation induction in anovulatory infertility and for increased follicle recruitment in ovulatory infertility.Letrozole appears to avoid the unfavorable effects on the endometrium frequently seen with antiestrogen use for ovulation induction.(Fertil Steril 2001;75:305-9.©2001 by American Society for Reproductive Medicine.) In women with World Health Organization type II anovulatory infertility, the treatment of first choice for the induction of ovulation is an antiestrogen, most commonly clomiphene citrate (CC) (1,2).However, 20%-25% of women are resistant to CC and do not ovulate.In addition, clinical data have revealed a discrepancy between ovulation and conception rates during CC treatment and a higher than expected incidence of miscarriage in conception cycles (3)(4)(5)(6).These observations have been attributed to the antiestrogenic mechanism of action of CC, which involves long-lasting estrogen receptor (ER) depletion.It also appears that CC accumulates in the body because of its long half-life (7).As a result, CC may have a negative effect on the quality and quantity of cervical mucus (8), on endometrial development (9), and on other as yet undetermined fertility factors (10,11). After failure of CC, gonadotropin preparations such as hMG or pure FSH have been used as a second-line treatment for ovulation induction.In women with polycystic ovary syndrome (PCOS), because of the high sensitivity of the ovaries to gonadotropin stimulation, treatment with hMG or pure FSH is difficult to control and characteristically induces several ovulatory follicles, leading to the risk of multiple pregnancies and ovarian hyperstimulation syndrome (OHSS) (12).Therefore, a simple oral treatment that could be used without risk of hyperstimulation and with minimal monitoring would be the preferred therapy.
What the sources say
- Not checked — no full text of the sourcecites [12] Kettel, 1993, Hypothalamic-pituitary-ovarian response to clomiphene citrate in women with polycystic ovary syndrome, Fertil Steril source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A claim is checked only against the cited paper’s full text, never its abstract, and none is available for its sources.
In the paper
“These aromatase inhibitors have a relatively short half-life compared with CC and therefore would be eliminated from the body rapidly (14,15).”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > Abstract Objective: To use aromatase inhibition for induction of ovulation in women in whom clomiphene citrate (CC) treatment was unsuccessful.Design: Prospective trial in infertility patients treated with CC.Setting: Two tertiary-referral infertility clinics associated with the Division of Reproductive Sciences, University of Toronto.Patient(s): Twelve patients with anovulatory polycystic ovary syndrome (PCOS) and 10 patients with ovulatory infertility, all of whom had previously received CC with an inadequate outcome (no ovulation and/or endometrial thickness of Յ0.5 cm).Intervention(s): The aromatase inhibitor letrozole was given orally in a dose of 2.5 mg on days 3-7 after menses.Main Outcome Measure(s): Occurrence of ovulation, endometrial thickness, and pregnancy rates.Result(s): With CC treatment in patients with PCOS, ovulation occurred in 8 of 18 cycles (44.4%), and all ovulatory cycles for the women included in this study had endometrial thickness of Յ0.5 cm.In 10 ovulatory patients, 15 CC cycles resulted in a mean number of 2.5 mature follicles, but all cycles had endometrial thickness of Յ0.5 cm on the day of hCG administration.With letrozole treatment in the same patients with PCOS, ovulation occurred in 9 of 12 cycles (75%) and pregnancy was achieved in 3 patients (25%).In the 10 patients with ovulatory infertility, letrozole treatment resulted in a mean number of 2.3 mature follicles and mean endometrial thickness of 0.8 cm.Pregnancy was achieved in 1 patient (10%).Conclusion(s): Oral administration of the aromatase inhibitor letrozole is effective for ovulation induction in anovulatory infertility and for increased follicle recruitment in ovulatory infertility.Letrozole appears to avoid the unfavorable effects on the endometrium frequently seen with antiestrogen use for ovulation induction.(Fertil Steril 2001;75:305-9.©2001 by American Society for Reproductive Medicine.) In women with World Health Organization type II anovulatory infertility, the treatment of first choice for the induction of ovulation is an antiestrogen, most commonly clomiphene citrate (CC) (1,2).However, 20%-25% of women are resistant to CC and do not ovulate.In addition, clinical data have revealed a discrepancy between ovulation and conception rates during CC treatment and a higher than expected incidence of miscarriage in conception cycles (3)(4)(5)(6).These observations have been attributed to the antiestrogenic mechanism of action of CC, which involves long-lasting estrogen receptor (ER) depletion.It also appears that CC accumulates in the body because of its long half-life (7).As a result, CC may have a negative effect on the quality and quantity of cervical mucus (8), on endometrial development (9), and on other as yet undetermined fertility factors (10,11). After failure of CC, gonadotropin preparations such as hMG or pure FSH have been used as a second-line treatment for ovulation induction.In women with polycystic ovary syndrome (PCOS), because of the high sensitivity of the ovaries to gonadotropin stimulation, treatment with hMG or pure FSH is difficult to control and characteristically induces several ovulatory follicles, leading to the risk of multiple pregnancies and ovarian hyperstimulation syndrome (OHSS) (12).Therefore, a simple oral treatment that could be used without risk of hyperstimulation and with minimal monitoring would be the preferred therapy.
What the sources say
- Not checked — no full text of the sourcecites [14] Lipton, 1995, Letrozole (CGS 20267), Cancer source
- Not checked — no full text of the sourcecites [15] Iveson, 1993, Phase I study of the oral nonsteroidal aromatase inhibitor CGS 20267 in postmenopausal patients with advanced breast cancer, Cancer Res source
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
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It may state two separate claims as one.
A claim is checked only against the cited paper’s full text, never its abstract, and none is available for its sources.
In the paper
“Continuous administration of letrozole up to 5 mg/d produced marked suppression of E 2 , estrone, and estrone sulfate, with very few side effects (14,15).”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > FERTILITY & STERILITY
What the sources say
- Not checked — no full text of the sourcecites [14] Lipton, 1995, Letrozole (CGS 20267), Cancer source
- Not checked — no full text of the sourcecites [15] Iveson, 1993, Phase I study of the oral nonsteroidal aromatase inhibitor CGS 20267 in postmenopausal patients with advanced breast cancer, Cancer Res source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“In addition, androgen accumulation in the follicle may stimulate insulin-like growth factor, along with other endocrine and paracrine factors, which may synergize with FSH to promote folliculogenesis (25)(26)(27).”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > FERTILITY & STERILITY
What the sources say
- Not matchedcites (25)(26)(27)
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
- Not matched
In the paper
“The absolute systemic bioavailability of letrozole after oral administration was 100% compared with the same dose given IV (19).”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > FERTILITY & STERILITY
What the sources say
- Not checked — no full text of the sourcecites [19] Sioufi, 1997, Absolute bioavailability of letrozole in healthy post-menopausal women, Biopharm Drug Dispos source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
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Probably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“Testosterone was found to augment follicular FSH receptor expression in primates, which suggests that androgens promote follicular growth and estrogen biosynthesis indirectly by amplifying FSH effects (22)(23)(24).”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > FERTILITY & STERILITY
What the sources say
- Not matchedcites (22)(23)(24)
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Not matched
A claim is checked only against the cited paper’s full text, never its abstract, and none is available for its sources.
In the paper
“Some investigators have proposed combined CC and low-dose glucocorticoid therapy for the treatment of CCresistant anovulation (28 -31).”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > FERTILITY & STERILITY
What the sources say
- Not checked — no full text of the sourcecites [28] Lobo, 1982, Clomiphene and dexamethasone in women unresponsive to clomiphene alone, Obstet Gynecol
- Not checked — no full text of the sourcecites [29] Singh, 1992, Clomiphene-dexamethasone treatment of clomiphene resistant women with and without the polycystic ovary syndrome, J Reprod Med
- Not checked — no full text of the sourcecites [30] Daly, 1984, A randomized study of dexamethasone in ovulation induction with clomiphene citrate, Fertil Steril source
- Not checked — no full text of the sourcecites [31] Diamant, 1980, Induction of ovulation by combined clomiphene citrate and dexamethasone treatment in clomiphene citrate nonresponders, Eur J Obstet Gynecol Reprod Biol source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“In addition, clinical data have revealed a discrepancy between ovulation and conception rates during CC treatment and a higher than expected incidence of miscarriage in conception cycles (3)(4)(5)(6).”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > Abstract Objective: To use aromatase inhibition for induction of ovulation in women in whom clomiphene citrate (CC) treatment was unsuccessful.Design: Prospective trial in infertility patients treated with CC.Setting: Two tertiary-referral infertility clinics associated with the Division of Reproductive Sciences, University of Toronto.Patient(s): Twelve patients with anovulatory polycystic ovary syndrome (PCOS) and 10 patients with ovulatory infertility, all of whom had previously received CC with an inadequate outcome (no ovulation and/or endometrial thickness of Յ0.5 cm).Intervention(s): The aromatase inhibitor letrozole was given orally in a dose of 2.5 mg on days 3-7 after menses.Main Outcome Measure(s): Occurrence of ovulation, endometrial thickness, and pregnancy rates.Result(s): With CC treatment in patients with PCOS, ovulation occurred in 8 of 18 cycles (44.4%), and all ovulatory cycles for the women included in this study had endometrial thickness of Յ0.5 cm.In 10 ovulatory patients, 15 CC cycles resulted in a mean number of 2.5 mature follicles, but all cycles had endometrial thickness of Յ0.5 cm on the day of hCG administration.With letrozole treatment in the same patients with PCOS, ovulation occurred in 9 of 12 cycles (75%) and pregnancy was achieved in 3 patients (25%).In the 10 patients with ovulatory infertility, letrozole treatment resulted in a mean number of 2.3 mature follicles and mean endometrial thickness of 0.8 cm.Pregnancy was achieved in 1 patient (10%).Conclusion(s): Oral administration of the aromatase inhibitor letrozole is effective for ovulation induction in anovulatory infertility and for increased follicle recruitment in ovulatory infertility.Letrozole appears to avoid the unfavorable effects on the endometrium frequently seen with antiestrogen use for ovulation induction.(Fertil Steril 2001;75:305-9.©2001 by American Society for Reproductive Medicine.) In women with World Health Organization type II anovulatory infertility, the treatment of first choice for the induction of ovulation is an antiestrogen, most commonly clomiphene citrate (CC) (1,2).However, 20%-25% of women are resistant to CC and do not ovulate.In addition, clinical data have revealed a discrepancy between ovulation and conception rates during CC treatment and a higher than expected incidence of miscarriage in conception cycles (3)(4)(5)(6).These observations have been attributed to the antiestrogenic mechanism of action of CC, which involves long-lasting estrogen receptor (ER) depletion.It also appears that CC accumulates in the body because of its long half-life (7).As a result, CC may have a negative effect on the quality and quantity of cervical mucus (8), on endometrial development (9), and on other as yet undetermined fertility factors (10,11). After failure of CC, gonadotropin preparations such as hMG or pure FSH have been used as a second-line treatment for ovulation induction.In women with polycystic ovary syndrome (PCOS), because of the high sensitivity of the ovaries to gonadotropin stimulation, treatment with hMG or pure FSH is difficult to control and characteristically induces several ovulatory follicles, leading to the risk of multiple pregnancies and ovarian hyperstimulation syndrome (OHSS) (12).Therefore, a simple oral treatment that could be used without risk of hyperstimulation and with minimal monitoring would be the preferred therapy.
What the sources say
- Not matchedcites (3)(4)(5)(6)
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Not matched
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In summary, the results of this preliminary study suggest that the aromatase inhibitor letrozole is an orally effective, inexpensive method for stimulating follicular development.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > FERTILITY & STERILITY
hedgeddirectn = 10- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“The subsequent increase in gonadotropin secretion could stimulate ovarian follicle development, as reported previously in the Bonnet monkey (20).”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > FERTILITY & STERILITY
What the sources say
- Not checked — no full text of the sourcecites [20] Shetty, 1997, Effect of estrogen deprivation on the reproductive physiology of male and female primates, J Steroid Biochem Mol Biol source
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“A 2-month washout period before the letrozole cycles was used to eliminate any posttreatment effect of CC.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > MATERIALS AND METHODS
plaindirectn = 22- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
In the paper
“Endometrial thickness was assessed as we have described previously (9) and as performed routinely in our clinic for the last 10 years.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > MATERIALS AND METHODS
What the sources say
- Not checked — no full text of the sourcecites [9] Gonen, 1990, Sonographic determination of an adverse effect of clomiphene citrate on endometrial growth, Hum Reprod source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“Other investigators have described the use of extended duration and higher doses of CC (32)(33)(34)(35).”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > FERTILITY & STERILITY
What the sources say
- Not matchedcites (32)(33)(34)(35)
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“Identical criteria were used for administration of hCG in both the CC-and letrozole-treated cycles.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > MATERIALS AND METHODS
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
The paper relies on this without support.
20%-25% of women are resistant to CC and do not ovulate.
“However, 20%-25% of women are resistant to CC and do not ovulate.”
The paper relies on this without support.
Letrozole is a specific, reversible, nonsteroidal aromatase inhibitor that suppresses estrogen biosynthesis.
“Letrozole (4,4Ј-[1H-1, 2, 4-triazol-1-ylmethylene]-bis-benzonitrile) is a specific, reversible, nonsteroidal aromatase inhibitor that suppresses estrogen biosynthesis.”
The paper relies on this without support.
The disposition of letrozole in healthy postmenopausal women is characterized by steady-state plasma concentrations in 4-8 hours and a half-life of approximately 45 hours.
“The disposition of letrozole in healthy postmenopausal women is characterized by steady-state plasma concentrations in 4 -8 hours and a half-life of approximately 45 hours.”
The paper relies on this without support.
CC is the most commonly prescribed medication for ovulation induction.
“CC is the most commonly prescribed medication for ovulation induction.”
The paper relies on this without support.
Women with ovulatory disorders who are resistant to standard doses of CC generally become candidates for gonadotropin therapy.
“Women with ovulatory disorders who are resistant to standard doses of CC generally become candidates for gonadotropin therapy.”
The paper relies on this without support.
Severe OHSS and the high risk of multiple pregnancy are major disadvantages of gonadotropin treatment, especially in young women with PCOS.
“However, severe OHSS and the high risk of multiple pregnancy are major disadvantages of gonadotropin treatment, especially in young women with PCOS.”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
In the citing paper
“Aromatase inhibitors were proposed as ovulation-inducing agents in 2001. 236”
From Assessment and management of polycystic ovary syndrome: Summary of an evidence-based guideline (2011) · cites this paper as [236]
In the citing paper
“Ovulation induction with letrozole is associated with an ovulation rate of 70%-84% and a pregnancy rate of 20%-27% per cycle.”
From A new era in ovulation induction (2006) · cites this paper as [50]
In the citing paper
“In a small study (50), 12 PCOS patients with inadequate response to CC were treated with letrozole.Of 12 patients, 9 (75%) ovulated, and 3 conceived; the mean endometrial thickness was 8.1 mm (6.2 mm with CC).”
From A new era in ovulation induction (2006) · cites this paper as [50]
In the citing paper
“Recently, it was suggested that letrozole, a specific reversible, nonsteroidal aromatase inhibitor that suppresses estrogen biosynthesis (16), can successfully replace clomiphene citrate in superovulation treatment of patients with unexplained infertility or polycystic ovarian disease and in poor responders (17,18).”
From Effects of letrozole on superovulation with gonadotropins in women undergoing intrauterine insemination (2003) · cites this paper as [17]
In the citing paper
“Two doses regimens have been tested (2.5 mg and 5 mg) with similar response (8,9).”
From A randomized trial of letrozole versus clomiphene citrate in women undergoing superovulation (2004) · cites this paper as [8]
In the citing paper
“Mitwally and Casper (8) used letrozole (2.5 mg daily for 5 days) in 12 women with inadequate response to CC. Ovulation occurred in 9 of 12 cycles and 3 patients conceived.”
From A randomized trial of letrozole versus clomiphene citrate in women undergoing superovulation (2004) · cites this paper as [8]
In the citing paper
“The ideal dose of letrozole for superovulation or ovulation induction is still unknown.”
From A randomized trial of letrozole versus clomiphene citrate in women undergoing superovulation (2004) · cites this paper as [8]
In the citing paper
“Compared with CC, letrozole is associated with a thicker endometrium (8).”
From A randomized trial of letrozole versus clomiphene citrate in women undergoing superovulation (2004) · cites this paper as [8]
In the citing paper
“In a selected population of women with a thin endometrium (mean, 5 mm) after clomiphene treatment, letrozole treatment in the early follicular phase resulted in a significant increase in midcycle endometrial thickness (mean, 9 mm) (21).”
From A randomized double-blind comparison of the effects of clomiphene citrate and the aromatase inhibitor letrozole on ovulatory function in normal women (2002) · cites this paper as [21]
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
Each contradiction between two passages listed here was confirmed by an independent check.
Rated major: it would touch a result — a value a result rests on, reported and recomputed p-values on opposite sides of the significance level, two passages that conflict with no sign which is right, or a cited work retracted before this paper was published.
In the paper
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > RESULTS
“Ovulation occurred in 8 cycles (44.4%) with an endometrial thickness of Յ0.5 cm.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > DISCUSSION
“Endometrial thickness (cm) on day of hCG 0.81 Ϯ 0.14 0.62 Ϯ 0.25 Ͻ.01 0.7-1.1 0.3-1.20.8 0.6”
Rated minor: it would not touch a result — a value no result rests on, a p-value that stays on the same side of the significance level, or a conflict that is clerical, resolved elsewhere in the paper, or outside its own findings.
In the paper
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > RESULTS
“However, the endometrial thickness was Յ0.5 cm in all cycles, and no pregnancy was achieved.”
§ Use of an aromatase inhibitor for induction of ovulation in patients with an inadequate response to clomiphene citrate > FERTILITY & STERILITY
“Endometrial thickness (cm) on day of hCG 0.89 Ϯ 0.12 0.5 Ϯ 0.1 Ͻ.001 0.7-1.1 0.3-0.6 0.9 0.5”
Citations
Cites
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Androgens stimulate early stages of follicular growth in the primate ovary
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Androgen and follicle stimulating hormone interactions in primate ovarian follicle development
Weil, S., Vendola, K., Zhou, J., & Bondy, C. A. (1999) · The Journal of Clinical Endocrinology & Metabolism · doi:10.1210/jcem.84.8.5929 · Cited by 592
Insulin-Like Growth Factors and Ovarian Follicular Development*
Giudice, L. C. (1992) · Endocrine Reviews · doi:10.1210/edrv-13-4-641 · Cited by 521
Weil, S. J., Vendola, K., Zhou, J., Adesanya, O. O., Wang, J., Okafor, J., & Bondy, C. A. (1998) · The Journal of Clinical Endocrinology & Metabolism · doi:10.1210/jcem.83.7.4917 · Cited by 359
Vendola, K., Zhou, J., Wang, J., Famuyiwa, O. A., Bievre, M., & Bondy, C. A. (1999) · Biology of Reproduction · doi:10.1095/biolreprod61.2.353 · Cited by 324
Effect of estrogen deprivation on the reproductive physiology of male and female primates
Shetty, G., Krishnamurthy, H., Krishnamurthy, H. N., Bhatnagar, A. S., & Moudgal, R. N. (1997) · The Journal of Steroid Biochemistry and Molecular Biology · doi:10.1016/s0960-0760(97)80008-8 · Cited by 306
Dunaif, A., Heindel, J. J., & Chang, R. (2002) · CRC Press eBooks · doi:10.3109/9780203910948 · Cited by 283
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Research works printed but not linked: 1
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Sorted by citations
Items 101–200 of 799
A historical perspective of aromatase inhibitors for ovulation induction
Casper, R. F., & Mitwally, M. F. (2012) · Fertility and Sterility · doi:10.1016/j.fertnstert.2012.10.008 · Cited by 64
Self-citationHashim, H. A., Shokeir, T. A., & Badawy, A. (2009) · Fertility and Sterility · doi:10.1016/j.fertnstert.2009.07.985 · Cited by 63
“Holzer H, Casper R, Tulandi T.”
BackgroundInfluentialRetractedAromatase Inhibitors for Ovulation Induction
Palomba, S. (2015) · The Journal of Clinical Endocrinology & Metabolism · doi:10.1210/jc.2014-4235 · Cited by 65
“In their pilot clinical studies in 2000 and 2001, despite many study limitations, Mitwally and Casper were the first to propose the use of AI letrozole to induce ovulation in women with PCOS and to demonstrate its efficacy in naive-therapy and/or CC-resistant patients (19, 20).”
BackgroundBadawy, A., Elnashar, A., & Totongy, M. (2008) · Fertility and Sterility · doi:10.1016/j.fertnstert.2008.06.013 · Cited by 63
RetractedEffect of clomiphene citrate on endometrium thickness and echogenic patterns
Dehbashi, S., Parsanezhad, M. E., Alborzi, S., & Zarei, A. (2003) · International Journal of Gynecology & Obstetrics · doi:10.1016/s0020-7292(02)00341-7 · Cited by 63
Franik, S., Le, Q.-K., Kremer, J. A. M., Kiesel, L., & Farquhar, C. M. (2022) · Cochrane Database of Systematic Reviews · doi:10.1002/14651858.cd010287.pub4 · Cited by 63
Polycystic ovarian syndrome – prognosis and outcomes
Hart, R. J., & Norman, R. J. (2006) · Best Practice & Research Clinical Obstetrics & Gynaecology · doi:10.1016/j.bpobgyn.2006.04.006 · Cited by 63
Li, S.-J., Zhang, Y., Chai, X., Nie, M., Zhou, Y., Chen, J., & Tao, G. (2013) · Archives of Gynecology and Obstetrics · doi:10.1007/s00404-013-3044-0 · Cited by 60
“In addition, letrozole treatment in combination with 75–150 U HMG failed to induce ovulation in 9 PCOS patients with basal antral follicle counts of more than 20 in all bilateral ovaries, and HRT was used (these patients were also excluded from the study).”
BackgroundResultInfluentialYıldırım, G., Attar, R., Özkan, F., Kumbak, B., Fıçıcıoğlu, C., & Yeşildağlar, N. (2009) · Fertility and Sterility · doi:10.1016/j.fertnstert.2009.09.021 · Cited by 62
Palomba, S., Falbo, A. I., & Zullo, F. (2009) · Current Opinion in Obstetrics & Gynecology · doi:10.1097/gco.0b013e328332d188 · Cited by 62
Biomaterials for Dental Implants: An Overview
Amarnath, G. S., Muddugangadhar, B. C., Tripathi, S., Suchismita, D., & Divya, M. S. (2011) · International Journal of Oral Implantology and Clinical Research · doi:10.5005/jp-journals-10012-1030 · Cited by 62
Baruah, J., Roy, K. K., Rahman, S. M., Kumar, S., Sharma, J. B., & Karmakar, D. (2008) · Archives of Gynecology and Obstetrics · doi:10.1007/s00404-008-0714-4 · Cited by 59
Mohsen, I. A., & Din, R. E. E. (2012) · Gynecological Endocrinology · doi:10.3109/09513590.2012.730569 · Cited by 59
“Letrozole administration in early follicular phase blocks estrogen syntheses by inhibiting aromatase enzyme that leads to increase in FSH secretion stimulating the recruitment and growth of antral follicles [22] Furthermore, letrozole causes temporary accumulation of androgens in the ovarian follicles by blocking the…”
BackgroundEmerging drugs for endometriosis
Fedele, L., & Berlanda, N. (2004) · Expert Opinion on Emerging Drugs · doi:10.1517/14728214.9.1.167 · Cited by 73
“5 mg letrozole in days 3 – 7 of the menstrual cycle is able to induce ovulation in anovulatory patients [67].”
BackgroundBadawy, A., Metwally, M., & Fawzy, M. (2007) · Reproductive BioMedicine Online · doi:10.1016/s1472-6483(10)61046-2 · Cited by 59
RetractedA brief update on the evidence supporting the treatment of infertility in polycystic ovary syndrome
Costello, M., Misso, M. L., Balen, A. H., Boyle, J. A., Devoto, L., Garad, R. M., Hart, R. J., Johnson, L., Jordan, C., Legro, R. S., et al. (2019) · Australian and New Zealand Journal of Obstetrics and Gynaecology · doi:10.1111/ajo.13051 · Cited by 58
Cancer and fertility preservation: fertility preservation in breast cancer patients
Maltaris, T., Weigel, M., Mueller, A., Schmidt, M., Seufert, R., Fischl, F., Koelbl, H., & Dittrich, R. (2008) · Breast Cancer Research · doi:10.1186/bcr1991 · Cited by 57
“The use of aromatase inhibitors for ovulation induction was first reported in 2001; letrozole was reported to provide superior results to clomiphene and was associated with 50% lower estradiol levels [ 57 ].”
BackgroundAromatase inhibitors: possible future applications
Karaer, Ö., Oruç, S., & Koyuncu, F. M. (2004) · Acta Obstetricia Et Gynecologica Scandinavica · doi:10.1111/j.0001-6349.2004.00562.x · Cited by 59
Aromatase Inhibitors: Rationale and Use in Breast Cancer
Osborne, C., & Tripathy, D. (2005) · Annual Review of Medicine · doi:10.1146/annurev.med.56.062804.103324 · Cited by 59
Aromatase inhibitors in the treatment of endometriosis
Słopień, R., & Męczekalski, B. (2016) · Menopause Review/Przegląd Menopauzalny · doi:10.5114/pm.2016.58773 · Cited by 56
“Aromatase inhibitors were first used in ovulation induction treatment in 2001 [26].”
MethodCurrent and experimental drug therapy for the treatment of polycystic ovarian syndrome
Corte, L. D., Foreste, V., Barra, F., Gustavino, C., Alessandri, F., Centurioni, M. G., Ferrero, S., Bifulco, G., & Giampaolino, P. (2020) · Expert Opinion on Investigational Drugs · doi:10.1080/13543784.2020.1781815 · Cited by 65
PCOS: an ovarian disorder that leads to dysregulation in the hypothalamic–pituitary–adrenal axis?
Doi, S. A. R., Towers, P. A., Scott, C., & Al-Shoumer, K. A. S. (2004) · European Journal of Obstetrics & Gynecology and Reproductive Biology · doi:10.1016/j.ejogrb.2004.06.024 · Cited by 57
“This has been confirmed recently by several workers with no apparent adverse effect on endometrial thickness or pattern at midcycle [38–40].”
BackgroundIrregular cycles and steroid hormones in polycystic ovary syndrome
Doi, S. A. R., Al-Zaid, M. M., Towers, P. A., Scott, C., & Al-Shoumer, K. A. S. (2005) · Human Reproduction · doi:10.1093/humrep/dei093 · Cited by 55
“For example, aromatase inhibitors have a similar effect with no apparent adverse effect on endometrial thickness or pattern at midcycle ( Mitwally and Casper, 2001, Mitwally and Casper, 2002; Fisher et al., 2002).”
BackgroundBarritt, J. A., Luna, M., Duke, M., et al. (2006) · Fertility and Sterility · doi:10.1016/j.fertnstert.2006.04.052 · Cited by 56
Whary, M. T., Cline, J. H., King, A. E., et al. (2000) · PubMed · Cited by 56
Jee, B. C., Ku, S., Suh, C. S., Kim, K. C., Lee, W. D., & Kim, S. H. (2006) · Fertility and Sterility · doi:10.1016/j.fertnstert.2006.02.070 · Cited by 57
The Use of Aromatase Inhibitors for Ovulation Induction and Superovulation
Pavone, M. E., & Bulun, S. E. (2013) · The Journal of Clinical Endocrinology & Metabolism · doi:10.1210/jc.2013-1328 · Cited by 57
Hu, Y., Chen, Y., Zhu, Y., & Huang, H. (2013) · Clinical Endocrinology · doi:10.1111/cen.12280 · Cited by 52
Mitwally, M. F., Casper, R. F., & Diamond, M. P. (2005) · Reproductive Biology and Endocrinology · doi:10.1186/1477-7827-3-54 · Cited by 55
Self-citationGregoriou, O., Vlahos, N., Konidaris, S., Papadias, K., Botsis, D. S., & Creatsas, G. K. (2007) · Fertility and Sterility · doi:10.1016/j.fertnstert.2007.06.099 · Cited by 54
Tsiami, A. P., Goulis, D. G., Sotiriadis, A., & Kolibianakis, E. M. (2021) · HORMONES · doi:10.1007/s42000-021-00289-z · Cited by 54
Current evidence supporting "letrozole" for ovulation induction
Kar, S. (2013) · Journal of Human Reproductive Sciences · doi:10.4103/0974-1208.117166 · Cited by 56
“Mitwally of Toronto General Hospital are credited for proposing the concept of aromatase inhibitors as an alternative to CC for OI, more than a decade ago.[1,2] They made attempts to synthesize orally active 4‐hydroxy androstenedione (40H‐A, the only known steroidal aromatase inhibitor).”
BackgroundLøssl, K., Andersen, C. Y., Loft, A. G., Freiesleben, N. L. C., Bangsbøll, S., & Andersen, A. N. (2008) · Human Reproduction · doi:10.1093/humrep/den131 · Cited by 53
“Since 2001, aromatase inhibitors have been used on an experimental basis for ovulation induction and for controlled ovarian stimulation (COS) in infertile women due to the drugs’ ability to increase endogenous gonadotrophin levels by blockage of estrogen synthesis (Mitwally and Casper, 2001).”
MethodLiu, C., Feng, G., Huang, W., Wang, Q., Yang, S., Tan, J., Fu, J., & Liu, D. (2017) · Gynecological Endocrinology · doi:10.1080/09513590.2017.1332174 · Cited by 59
“LE was first reported to be used as an ovulation inducer for PCOS patients in 2001 [4].”
Hu, S., Yu, Q., Wang, Y., Wang, M., Xia, W., & Zhu, C. (2018) · Archives of Gynecology and Obstetrics · doi:10.1007/s00404-018-4688-6 · Cited by 53
“The first report of LE for clinical ovulation induction was published in 2001 [14].”
BackgroundBarroso, G., Menocal, G., Felix, H., Ruiz, J. C. R., Arslan, M., & Oehninger, S. (2006) · Fertility and Sterility · doi:10.1016/j.fertnstert.2006.03.044 · Cited by 53
To Block Estrogen's Synthesis or Action: That Is the Question
Santen, R. J. (2002) · The Journal of Clinical Endocrinology & Metabolism · doi:10.1210/jcem.87.7.8589 · Cited by 54
“Further clinical studies are also required to fully validate the observations from the single study of letrozole in women failing to respond adequately to clomiphene citrate (14).”
BackgroundRay, P. B., Ray, A., & Chakraborti, P. S. (2011) · Archives of Gynecology and Obstetrics · doi:10.1007/s00404-011-2091-7 · Cited by 54
“These complications are attributed to the anti-estrogenic effect and the relatively longer half-life of clomiphene citrate, thus decreasing endometrial thickness by its longterm effect in decreasing the number of oestrogen receptors [13].”
BackgroundLetrozole or clomiphene citrate as first line for anovulatory infertility: a debate
Kamath, M. S., & George, K. (2011) · Reproductive Biology and Endocrinology · doi:10.1186/1477-7827-9-86 · Cited by 50
“Letrozole, an aromatase inhibitor, was introduced into infertility practice in the year 2000 and is regarded as a second line treatment option, particularly in women with clomiphene resistance [3,4].”
BackgroundPolycystic ovaries and infertility: Our experience
Rajashekar, L., Krishna, D., & Patil, M. (2008) · Journal of Human Reproductive Sciences · doi:10.4103/0974-1208.44113 · Cited by 53
Palatnik, A., Strawn, E., Szabó, A., et al. (2012) · Fertility and Sterility · doi:10.1016/j.fertnstert.2012.02.018 · Cited by 51
Rani, S., Raheja, K., Luxami, V., & Paul, K. (2021) · Bioorganic Chemistry · doi:10.1016/j.bioorg.2021.105017 · Cited by 53
Okman, T. K., Küçük, M., & Altaner, Ş. (2003) · Fertility and Sterility · doi:10.1016/j.fertnstert.2003.05.002 · Cited by 50
Xi, W., Yang, Y.-K., Mao, H. Z., Zhao, X., Liu, M., & Fu, S. (2016) · Journal of Ovarian Research · doi:10.1186/s13048-016-0214-2 · Cited by 47
“There are 20–25 % of women, however, remain anovulatory after receiving CC medication [8] and the exact cause of CC failure in some patients remain uncertain.”
BackgroundPharmacology of medications used for ovarian stimulation
Quaas, A. M., & Legro, R. S. (2018) · Best Practice & Research Clinical Endocrinology & Metabolism · doi:10.1016/j.beem.2018.10.002 · Cited by 51
“Given that aromatase inhibitors dramatically lower systemic estrogen concentrations, investigators attempted to use them for ovulation induction by preventing estrogen negative feedback on FSH [40,41].”
BackgroundPotential role of aromatase inhibitors in the treatment of endometriosis
Hashim, H. A. (2014) · International Journal of Women s Health · doi:10.2147/ijwh.s34684 · Cited by 46
“59 Letrozole’s ovulation-inducing effects have been attributed to the inhibition of androgen–estrogen conversion, thus releasing the hypothalamus–pituitary axis from negative feedback and increasing secretion of pituitary FSH. Additionally, increased follicular sensitivity to FSH owing to increased…”
Badawy, A., Mosbah, A., Tharwat, A., & Eid, M. (2009) · Fertility and Sterility · doi:10.1016/j.fertnstert.2008.04.065 · Cited by 45
RetractedNew advances in ovulation induction
Kafy, S., & Tulandi, T. (2007) · Current Opinion in Obstetrics & Gynecology · doi:10.1097/gco.0b013e3280c60c9a · Cited by 47
Cost-effectiveness of aromatase inhibitor co-treatment for controlled ovarian stimulation
Bedaiwy, M. A., Forman, R., Mousa, N. A., Inany, H., & Casper, R. F. (2006) · Human Reproduction · doi:10.1093/humrep/del273 · Cited by 46
“Recently, aromatase inhibitors (letrozole and anastrozole) have been tested successfully as ovulation-inducing agents with an average cost of $100 per cycle (Mitwally and Casper, 2001).”
BackgroundInfluentialSelf-citationWallace, K. L., Johnson, V., Sopelak, V. M., & Hines, R. S. (2011) · Fertility and Sterility · doi:10.1016/j.fertnstert.2011.07.1092 · Cited by 45
“These data are in keeping with previous reports showing that letrozole is associated with a thicker endometrium leading to improved vascularization, as shown with Doppler studies (4, 7).”
MethodResultEspinola, M. S. B., Laganà, A. S., Bilotta, G., Gullo, G., Aragona, C., & Unfer, V. (2021) · American Journal of Case Reports · doi:10.12659/ajcr.932722 · Cited by 44
Lazer, T., Dar, S., Shlush, E., Kudmani, B. S. A., Quach, K., Sojecki, A., GLASS, K. B., Sharma, P., Baratz, A. Y., & Librach, C. L. (2014) · International Journal of Reproductive Medicine · doi:10.1155/2014/581451 · Cited by 44
“In addition, adjunctive growth hormone is advocated by some studies [1, 7] while aromatase inhibitors have also been suggested in other studies [8].”
ResultFertility and Reproductive Disorders in Female Solid Organ Transplant Recipients
Douglas, N. C., Shah, M., & Sauer, M. V. (2007) · Seminars in Perinatology · doi:10.1053/j.semperi.2007.09.002 · Cited by 44
Risk of foetal harm with letrozole use in fertility treatment: a systematic review and meta-analysis
Pundir, J., Achilli, C., Bhide, P., Sabatini, L., Legro, R. S., Rombauts, L. J. F., Teede, H. J., Coomarasamy, A., Zamora, J., & Thangaratinam, S. (2020) · Human Reproduction Update · doi:10.1093/humupd/dmaa055 · Cited by 45
Kamath, M. S., Aleyamma, T. K., Chandy, A., & George, K. (2010) · Fertility and Sterility · doi:10.1016/j.fertnstert.2010.06.008 · Cited by 44
Eijkemans, M. J. C., Polinder, S., Mulders, A. G. M. G. J., Laven, J. S. E., Habbema, J. D. F., & Fauser, B. C. J. M. (2005) · Human Reproduction · doi:10.1093/humrep/dei164 · Cited by 44
“Each abstract contains a brief summary of the methods, the results and conclusions followed by a detailed critical assessment on the reliability of the study and the conclusions drawn.”
MethodEstrogen and Antiestrogen Effects on Neonatal Ovine Uterine Development1
Carpenter, K. D., Gray, C. A., Bryan, T. M., Welsh, T. H., & Spencer, T. E. (2003) · Biology of Reproduction · doi:10.1095/biolreprod.103.015990 · Cited by 44
“5 mg CGS 20267 was effective in inducing ovulation [33].”
BackgroundGanesh, A., Chauhan, N., Das, S. K., et al. (2013) · Systems Biology in Reproductive Medicine · doi:10.3109/19396368.2013.862316 · Cited by 43
“Letrozole, a highly selective aromatase inhibitor (AI), has emerged as a promising new alternative to clomiphene citrate (CC) as an effective ovulation inducing agent in anovulatory and ovulatory infertile women [Mitwally and Casper 2001; Badawy et al. 2007].”
BackgroundTshzmachyan, R., & Hambartsoumian, E. (2019) · Journal of Gynecology Obstetrics and Human Reproduction · doi:10.1016/j.jogoh.2019.101643 · Cited by 43
Pregnancy Considerations in Women With Polycystic Ovary Syndrome
Legro, R. S. (2007) · Clinical Obstetrics & Gynecology · doi:10.1097/grf.0b013e31803057ed · Cited by 43
Polycystic ovary syndrome: chemical pharmacotherapy
Rocca, M. L., Venturella, R., Mocciaro, R., Cello, A. D., Sacchinelli, A., Russo, V. M., Trapasso, S., Zullo, F., & Morelli, M. (2015) · Expert Opinion on Pharmacotherapy · doi:10.1517/14656566.2015.1047344 · Cited by 41
Bayoumi, Y. A., Dakhly, D. M. R., Bassiouny, Y. A., et al. (2015) · International Journal of Gynecology & Obstetrics · doi:10.1016/j.ijgo.2015.05.034 · Cited by 42
“Published by Elsevier I the use of adjunctive growth hormone (GH) [1,3,4] or aromatase inhibitors [6,7].”
BackgroundMethodQuaas, A. M., Gavrizi, S. Z., Peck, J. D., Diamond, M. P., Legro, R. S., Robinson, R. D., Casson, P. R., Christman, G. M., Zhang, H., & Hansen, K. R. (2020) · Fertility and Sterility · doi:10.1016/j.fertnstert.2020.07.030 · Cited by 44
Misoprostol With or Without Letrozole Pretreatment for Termination of Pregnancy
Lee, V. C. Y., Ng, E. H. Y., Yeung, W. S. B., & Ho, P. C. (2011) · Obstetrics and Gynecology · doi:10.1097/aog.0b013e3182073fbf · Cited by 41
Yu, J., Ma, Y., Wu, Z., Li, Y., Tang, L., Li, Y., & Deng, B. (2014) · Archives of Gynecology and Obstetrics · doi:10.1007/s00404-014-3396-0 · Cited by 42
“Recently, letrozole, an aromatase inhibitor, has been widely used as a potential ovulation induction agent for PCOS [27].”
BackgroundAromatase inhibitors for ovulation induction and ovarian stimulation
Lee, V. C. Y., & Ledger, W. J. (2011) · Clinical Endocrinology · doi:10.1111/j.1365-2265.2011.04006.x · Cited by 42
Hashim, H. A., RAKHAWY, M. E., & Elaal, I. A. (2011) · Acta Obstetricia Et Gynecologica Scandinavica · doi:10.1111/j.1600-0412.2011.01346.x · Cited by 43
“Mitwally and Casper (20) showed that letrozole was associated with a thicker endometrium when compared with CC.”
BackgroundDuhan, N., Madaan, S., & Sen, J. (2013) · European Journal of Obstetrics & Gynecology and Reproductive Biology · doi:10.1016/j.ejogrb.2013.09.010 · Cited by 40
Physiology and Pathology of the Female Reproductive Axis
Bulun, S. E. (2011) · Elsevier eBooks · doi:10.1016/b978-1-4377-0324-5.00017-1 · Cited by 40
Use of clomiphene citrate in women
(2006) · Fertility and Sterility · doi:10.1016/j.fertnstert.2006.08.023 · Cited by 41
Use of aromatase inhibitors in practice of gynecology
Usluoğullari, B., Duvan, C. Z., & Usluoğulları, C. A. (2015) · Journal of Ovarian Research · doi:10.1186/s13048-015-0131-9 · Cited by 40
“Some studies have showed that letrozole use in women resistant to clomiphene can induce ovulation in more patients compared to clomiphene [45].”
BackgroundEruption Chronology in Children: A Cross-sectional Study
Verma, N., Bansal, A., Tyagi, P., Jain, A., Tiwari, U., & Gupta, R. (2017) · International Journal of Clinical Pediatric Dentistry · doi:10.5005/jp-journals-10005-1450 · Cited by 40
Su, Y.-N., Wang, M., Yang, J.-P., Wu, X.-L., Xia, M., Bao, M., Ding, Y., Feng, Q., & Fu, L. (2023) · Frontiers in Endocrinology · doi:10.3389/fendo.2023.1122709 · Cited by 37
Mehdinejadiani, S., Amidi, F., Mehdizadeh, M., Barati, M., Pazhohan, A., Alyasin, A., Mehdinejadiani, K., & Sobhani, A. (2018) · Biology of Reproduction · doi:10.1093/biolre/ioy187 · Cited by 36
Polyzos, N. P., Tsappi, M., Mauri, D., Atay, V., Cortinovis, I., & Casazza, G. (2008) · Fertility and Sterility · doi:10.1016/j.fertnstert.2007.10.016 · Cited by 37
Nejad, E. S. T., Abediasl, Z., Rashidi, B. H., Nekoo, E. A., Shariat, M., & Amirchaghmaghi, E. (2008) · Journal of Assisted Reproduction and Genetics · doi:10.1007/s10815-008-9209-2 · Cited by 37
“aromatase inhibitor has been investigated as a potential ovulation induction agent [11].”
BackgroundSurface Modifications for Endosseous Dental Implants
Shetty, O. K., Parekh, R., & Tabassum, R. (2012) · International Journal of Oral Implantology and Clinical Research · doi:10.5005/jp-journals-10012-1078 · Cited by 38
Roles of estrogen and its receptors in polycystic ovary syndrome
Xu, Y., Zhang, Z., Wang, R., Xue, S., Ying, Q., & Jin, L. (2024) · Frontiers in Cell and Developmental Biology · doi:10.3389/fcell.2024.1395331 · Cited by 38
“Letrozole is an aromatase inhibitor and was fi rst used to induce ovulation in 2001 in women exhibiting CC resistance (Mitwally and Casper, 2001).”
MethodLuteal phase oestradiol suppression by letrozole: a pilot study in oocyte donors
Fatemi, H. M., Popovic-Todorovic, B., Donoso, P., Papanikolaou, E. G. E., Smitz, J. E. J., & Devroey, P. (2008) · Reproductive BioMedicine Online · doi:10.1016/s1472-6483(10)60212-x · Cited by 36
“5 mg/day has been used successfully for ovulation induction (Mitwally and Casper, 2001; Fatemi et al., 2003).”
MethodXue, X., Liu, S., Yang, Y.-K., Xiaoning, L., Xi, W., & Mao, H. Z. (2015) · Drug Design Development and Therapy · doi:10.2147/dddt.s83259 · Cited by 38
ACOG Committee Opinion No. 738: Aromatase Inhibitors in Gynecologic Practice
(2018) · Obstetrics and Gynecology · doi:10.1097/aog.0000000000002640 · Cited by 36
Tredway, D. R., Buraglio, M., Hemsey, G., & Denton, G. (2004) · Fertility and Sterility · doi:10.1016/j.fertnstert.2004.04.059 · Cited by 35
What can the clinician do to improve implantation?
Boomsma, C. M., & Macklon, N. (2006) · Reproductive BioMedicine Online · doi:10.1016/s1472-6483(10)61034-6 · Cited by 35
“Rather than antagonizing oestrogen feedback activity at the hypothalamic−pituitary axis, as achieved with clomiphene citrate, this approach reduces the amount of oestrogens synthesized, thereby increasing gonadotrophin secretion and stimulating follicular growth (Mitwally and Casper, 2001).”
BackgroundArtini, P. G., Obino, M. E. R., Sergiampietri, C., Pinelli, S., Papini, F., Casarosa, E., & Cela, V. (2018) · Expert Review of Endocrinology & Metabolism · doi:10.1080/17446651.2018.1431122 · Cited by 35
“Aromatase inhibitors Aromatase Inhibitors (AIs) are a class of drugs introduced for ovulation induction in 2001 [67], that (in particular letrozole) might be as effective as CC; they have a short half-life elimination time of 48 h, so they have fewer adverse effects on estrogen target tissues such as endometrium and c…”
BackgroundFoda, A. A., & Aal, I. A. A. (2012) · Middle East Fertility Society Journal · doi:10.1016/j.mefs.2012.09.001 · Cited by 34
A randomized trial of ovulation induction with two different doses of Letrozole in women with PCOS
Ramezanzadeh, F., Nasiri, R., Yazdi, M. S., & Baghrei, M. (2011) · Archives of Gynecology and Obstetrics · doi:10.1007/s00404-011-1951-5 · Cited by 33
“Letrozole, a non-steroidal aromatase inhibitor, has been introduced as a new treatment option, which can challenge CC for ovulation induction in anovulatory women [10, 11 ].”
BackgroundMukherjee, S., Sharma, S., & Chakravarty, B. (2012) · Journal of Human Reproductive Sciences · doi:10.4103/0974-1208.101014 · Cited by 34
“The success of aromatase inhibition by letrozole in inducing ovulation in anovulatory women with PCOS [5] and augmenting ovulation in ovulatory women in unexplained infertility[6] has been reported previously.”
BackgroundWhat role of estrogens in ovarian stimulation
Laven, J. S. E., & Fauser, B. C. J. M. (2006) · Maturitas · doi:10.1016/j.maturitas.2006.04.022 · Cited by 34
Parton, M., & Smith, I. E. (2008) · Journal of Clinical Oncology · doi:10.1200/jco.2007.14.3016 · Cited by 34
Seyedoshohadaei, F. (2016) · JOURNAL OF CLINICAL AND DIAGNOSTIC RESEARCH · doi:10.7860/jcdr/2016/20954.8324 · Cited by 33
Thakur, S., & Habib, R. (2017) · International Journal of Clinical Pediatric Dentistry · doi:10.5005/jp-journals-10005-1442 · Cited by 33
Letrozole versus human menopausal gonadotrophin in women undergoing intrauterine insemination
Baysoy, A., Serdaroğlu, H., Jamal, H., Karatekeli, E., Özörnek, H., & Attar, E. (2006) · Reproductive BioMedicine Online · doi:10.1016/s1472-6483(10)60617-7 · Cited by 33
Badawy, A., Aal, I. A., & Abulatta, M. (2008) · Fertility and Sterility · doi:10.1016/j.fertnstert.2007.08.034 · Cited by 34
RetractedOvarian drilling in polycystic ovary syndrome: Long term pregnancy rate
Debras, É., Fernandez, H., Neveu, M.-E., Deffieux, X., & Capmas, P. (2019) · European Journal of Obstetrics & Gynecology and Reproductive Biology X · doi:10.1016/j.eurox.2019.100093 · Cited by 32
“Aromatase inhibitor has been shown to be effective in restoring ovulation and pregnancy instead of the CC [12,13].”
BackgroundShen, M.-S., Wang, C., Chen, C., & Tzeng, C. (2013) · Journal of obstetrics and gynaecology research · doi:10.1111/j.1447-0756.2012.02070.x · Cited by 32
Hashim, H. A., Mashaly, A. E.-M., & Badawy, A. (2010) · Archives of Gynecology and Obstetrics · doi:10.1007/s00404-010-1566-2 · Cited by 32
“In other trials, Mitwally and Casper [14] had ovulatory rate of 75%, Al-Omari et al.”
BackgroundInfluentialRetractedDehbashi, S., Dehbashi, S., Kazerooni, T., Robati, M., Alborzi, S., & Shadman, A. (2009) · DOAJ (DOAJ: Directory of Open Access Journals) · Cited by 32
Costello, M., Garad, R. M., Hart, R. J., Homer, H. A., Johnson, L., Jordan, C., Mocanu, E. V., Qiao, J., Rombauts, L. J. F., Teede, H. J., et al. (2019) · Medical Sciences · doi:10.3390/medsci7090095 · Cited by 32
“Letrozole, an aromatase inhibitor, was first proposed as an ovulation inducing drug in anovulatory PCOS women in 2001 Table S1 [21].”
BackgroundThe Clinical Manifestations of Polycystic Ovary Syndrome (PCOS) and The Treatment Options
Karkera, S., Agard, E., & Sankova, L. (2023) · European Journal of Biology and Medical Science Research · doi:10.37745/ejbmsr.2013/vol11n15791 · Cited by 35
Liu, A., Zheng, C., Lang, J., & Chen, W. (2014) · Journal of obstetrics and gynaecology research · doi:10.1111/jog.12393 · Cited by 31
“The increase in FSH secretion stimulates the recruitment and growth of antral follicles.(33) Furthermore, letrozole causes temporary accumulation of androgens in the ovarian follicles which increase the sensitivity of the growing follicles to FSH by increasing the expression of FSH receptors.”
Background
Metadata
- Authors
- Mitwally, M. F. M., & Casper, R. F.
- Affiliations
- Mount Sinai Hospital (CA)
- University of Toronto (CA)
- Corresponding author
- Casper, Robert F
- ORCID
- Casper, Robert F
- Venue
- Fertility and Sterility
- Publisher
- Elsevier BV
- Published
- 2001-02
- Volume
- 75
- Issue
- 2
- Pages
- 305-309
- ISSN
- 0015-0282 (ISSN-L)
- OpenAlex
- W2165232862
- Cited by
- 800
- References
- 45
- Citations by year
- 2026: 7 · 2025: 10 · 2024: 13 · 2023: 20 · 2022: 28 · 2021: 26 · 2020: 23 · 2019: 22 · 2018: 25 · 2017: 56 · 2016: 24 · 2015: 69 · 2014: 49 · 2013: 52 · 2012: 63
- FWCI
- 14.93
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Licence
- Locations
- Fertility and Sterility (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Health Sciences › Medicine › Reproductive Medicine › Ovarian function and disorders
- Health Sciences › Medicine › Reproductive Medicine › Reproductive Biology and Fertility
- Health Sciences › Medicine › Reproductive Medicine › Reproductive Health and Technologies
- Keywords
- letrozole, aromatase inhibitors, ovulation induction, polycystic ovary syndrome, ovulatory infertility, anovulatory infertility, endometrial thickness, pregnancy rate, follicle recruitment
- MeSH terms
- Letrozole, Anovulation, Endometrium, Enzyme Inhibitors, Estradiol, Female, Chorionic Gonadotropin, Humans, Infertility, Female, Luteinizing Hormone, Nitriles, Ovulation Induction, Polycystic Ovary Syndrome, Pregnancy, Prospective Studies, Triazoles, Aromatase Inhibitors
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