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Cited by 29Diabetes Management and ResearchDiabetes, Cardiovascular Risks, and LipoproteinsDiabetes Management and Education

Menstrual Cycle, Glucose Control and Insulin Sensitivity in Type 1 Diabetes: A Systematic Review

Open access
Gamarra, Elena, Trimboli, Pierpaolo·2023·Journal of Personalized Medicine
DOI 10.3390/jpm13020374PMC PMC9962060
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Abstract

The correlation between the menstrual cycle and glucose control in type 1 diabetes has been the focus of several studies since the 1920s, but a few critical aspects made it particularly challenging to reach conclusive evidence. The aim of this systematic review is to reveal more solid information about the impact of the menstrual cycle on glycaemic outcomes and insulin sensitivity in type 1 diabetes and highlight the less researched areas. The literature was searched by two authors independently using PubMed/MEDLINE, Embase and Scopus (last search on 2 November 2022). The retrieved data did not allow us to perform a meta-analysis. We included 14 studies published between 1990 and 2022, with sample sizes from 4 to 124 patients. We found a wide heterogeneity in the definition of the menstrual cycle phases, glucose metrics, techniques for determining insulin sensitivity, hormonal assessment and other interfering factors considered, with an overall high risk of bias. There is no conclusive evidence, and published data do not allow us to achieve quantitative results. In a subset of patients, a possible worsening of insulin sensitivity and hyperglycaemia in the luteal phase could be observed. From the clinical standpoint, a cautious strategy based on patient-specific patterns can be considered until new, solid evidence is obtained.

AI snapshot

Written from the paper’s full text.

TL;DR

This systematic review found no conclusive evidence on the impact of the menstrual cycle on glycaemic outcomes and insulin sensitivity in type 1 diabetes, and the retrieved data did not allow a meta-analysis. In a subset of patients, insulin sensitivity may worsen and hyperglycaemia may increase in the luteal phase compared with the follicular phase.

Key findings

  • The review included 14 studies published between 1990 and 2022, with sample sizes from 4 to 124 patients and 1 to 6.5 menstrual cycles observed per patient (total 6 to 168 menstrual cycles).
  • Nine studies showed worsening or higher risk of hyperglycaemia in the luteal phase versus the follicular phase, while two studies showed unchanged glucose metrics across menstrual cycle phases.
  • Four studies showed worsening insulin sensitivity in the luteal phase compared with the follicular phase, while two studies showed absence of statistically significant differences in insulin sensitivity across phases.
  • Overall risk of bias was high, with wide heterogeneity in menstrual cycle phase definitions, glucose metrics, insulin sensitivity techniques, hormonal assessment, and other interfering factors.

Methods

  • Systematic review conducted according to PRISMA; PubMed/MEDLINE, Embase, and Scopus were searched with no beginning date limit and updated until 2 November 2022; two authors independently searched, screened, reviewed full texts, and selected articles, with discordances resolved by consensus.
  • Eligible studies were original articles describing variations in glucose control and/or insulin sensitivity during the menstrual cycle in women with type 1 diabetes; case reports were excluded; 14 studies were included after exclusions.
  • Risk of bias was independently assessed with the National Heart, Lung and Blood Institute Quality Assessment Tool for Observational Studies; findings were summarized qualitatively because a meta-analysis could not be performed.

Limitations

  • The paper states that the retrieved data did not allow a meta-analysis, that there was wide heterogeneity in menstrual cycle phase definition, glucose metrics, insulin sensitivity determination, hormonal assessment, and interfering factors, and that overall risk of bias was high, especially concerning sample size, power analysis, timeframe, exposure definition and assessment, and potential confounding variables.
  • The paper states that sample sizes were generally small, methods to define menstrual cycle phases and duration were heterogeneous, glycaemic metrics were heterogeneous with only a few studies using CGM metrics as recommended by international guidelines and often over limited observation periods, insulin sensitivity evaluation methods were questionable, and insulin sensitivity referred to daytime, night-time, or both in different studies.
  • The paper also states that the prevalence of the “menstrual cycle phenomenon” among women with type 1 diabetes is unclear, data from individual studies are not generalizable to a large population, the phenotype of luteal glycaemic worsening is unclear, and the effects of oestrogen, progesterone, and other hormones on insulin sensitivity and glycaemic parameters remain unresolved.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.3390/jpm13020374

Cites

39 of 39 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

11 of 59 cited sources checked · 5 supported · 1 flagged · accuracy not yet measured

  • Findingown data

    Fourteen studies were included in the systematic review.

    “We included 14 studies published between 1990 and 2022, with sample sizes from 4 to 124 patients.”
    • Also stated in: § 3.1. Eligible Articles · plain
      “Finally, 14 studies [7,10,11,12,13,14,15,16,20,21,22,23] were included in the systematic review (Figure 1).”
    Quote in the paperNot a substantial claim3 of 10 sources checked
    • cites [7] Moberg, 1995, Day-to-day variation of insulin sensitivity in patients with type 1 diabetes: Role of gender and menstrual cycle, Diabet. Med. source
    • cites [10] Tatulashvili, 2022, Ambulatory glucose profile according to different phases of the menstrual cycle in women living with type 1 diabetes, J. Clin. Endocrinol. Metab. source

      The Participants’ Characteristics section (page not provided) describes an original study of 24 women and 62 menstrual cycles, not a systematic review of 14 studies. The cited paper therefore does not support the attributed study count or the stated range of study sample sizes. (LLM, conf=0.88)

      Checked by a reasoning model — may be wrong.

      Experimental — accuracy not yet measured
    • cites [11] Lundman, 1994, Metabolic control, food intake and mood during the menstrual cycle in patients with insulin-dependent diabetes, Int. J. Nurs. Stud. source
    • cites [12] Brown, 2015, Fluctuation of hyperglycemia and insulin sensitivity are linked to menstrual cycle phases in women with type 1 diabetes, J. Diabetes Sci. Technol. source

      The Study Design and Subjects section describes a prospective trial that recruited 15 women, and the Results report that 12 completed it. The cited paper does not report a systematic review or its number of included studies (searched for 14 studies and systematic-review inclusion). The citing sentence’s “we included” appears to describe the citing authors’ own review, which this source cannot verify. (LLM, conf=0.77)

      Experimental — accuracy not yet measured
    • cites [13] Goldner, 2004, Cyclic changes in glycemia assessed by continuous glucose monitoring system during multiple complete menstrual cycles in women with type 1 diabetes, Diabetes Technol. Ther. source
    • cites [14] Lunt, 1996, Self-reported changes in capillary glucose and insulin requirements during the menstrual cycle, Diabet. Med. source
    • cites [15] Widom, 1992, Alteration in glucose metabolism during menstrual cycle in women with IDDM, Diabetes Care source
    • cites [16] Macdonald, 1990, Effect of phase of menstrual cycle on insulin sensitivity, peripheral blood flow and cardiovascular responses to hyperinsulinaemia in young women with type 1 diabetes, Diabet. Med. source
    • cites [20] Diaz, 2022, Insulin replacement across the menstrual cycle in women with type 1 diabetes: An in-silico assessment of the need for ad-hoc technology, Diabetes Technol. Ther. source
    • cites [21] Levy, 2022, Insulin delivery and glucose variability throughout the menstrual cycle on closed loop control for women with type 1 diabetes, Diabetes Technol. Ther. source

      The Results describe a substudy of 16 women, not a systematic review. Neither the Results nor the other passages found in our copy state how many studies the citing authors included; the number 14 refers to cycles in a participant range, not studies. (LLM, conf=0.78)

      Experimental — accuracy not yet measured
  • Premisecitation

    There is a lack of uniformity for estimating insulin sensitivity in type 1 diabetes.

    “a lack of uniformity for estimating insulin sensitivity (IS) [3,4,5,6,7]”
    Quote in the paperSubstantial claim1 of 5 sources checked
    • cites [3] Matsuda, 1999, Insulin sensitivity indices obtained from oral glucose tolerance testing: Comparison with the euglycemic insulin clamp, Diabetes Care source
    • cites [4] Bergman, 1979, Quantitative estimation of insulin sensitivity, Am. J. Physiol. source
    • cites [5] Gutch, 2015, Assessment of insulin sensitivity/resistance, Indian J. Endocrinol. Metab. source

      The Introduction (page unavailable) describes multiple indices for estimating insulin sensitivity and says their clinical use is limited by a lack of reference values. That supports a general concern about uniform estimation, but the paper does not establish that this lack of uniformity applies specifically to type 1 diabetes. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites [6] Januszewski, 2020, Estimated insulin sensitivity in type 1 diabetes adult using clinical and research biomarkers, Diabetes Res. Clin. Pract. source
    • cites [7] Moberg, 1995, Day-to-day variation of insulin sensitivity in patients with type 1 diabetes: Role of gender and menstrual cycle, Diabet. Med. source
  • Premisecitation

    The pathophysiological mechanism underlying insulin sensitivity changes observed during different phases of the menstrual cycle remains unclear.

    “However, the literature in this field is discordant, and the pathophysiological mechanism underlying IS changes observed during different phases of the MC remains still unclear [12,13,14].”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [12] Brown, 2015, Fluctuation of hyperglycemia and insulin sensitivity are linked to menstrual cycle phases in women with type 1 diabetes, J. Diabetes Sci. Technol. source
    • cites [13] Goldner, 2004, Cyclic changes in glycemia assessed by continuous glucose monitoring system during multiple complete menstrual cycles in women with type 1 diabetes, Diabetes Technol. Ther. source
    • cites [14] Lunt, 1996, Self-reported changes in capillary glucose and insulin requirements during the menstrual cycle, Diabet. Med. source
  • Premisecitation

    The literature on the relationship between the menstrual cycle and insulin sensitivity/glycaemic control in type 1 diabetes is discordant.

    “However, the literature in this field is discordant, and the pathophysiological mechanism underlying IS changes observed during different phases of the MC remains still unclear [12,13,14].”
    • Also stated in: § 1. Introduction · hedged
      “In fact, some authors found that IS might hold a role, but these data were not confirmed (or not evaluated) by other studies [7,15,16].”
    Quote in the paperSubstantial claim1 of 6 sources checked
    • cites [12] Brown, 2015, Fluctuation of hyperglycemia and insulin sensitivity are linked to menstrual cycle phases in women with type 1 diabetes, J. Diabetes Sci. Technol. source
    • cites [13] Goldner, 2004, Cyclic changes in glycemia assessed by continuous glucose monitoring system during multiple complete menstrual cycles in women with type 1 diabetes, Diabetes Technol. Ther. source
    • cites [14] Lunt, 1996, Self-reported changes in capillary glucose and insulin requirements during the menstrual cycle, Diabet. Med. source
    • cites [7] Moberg, 1995, Day-to-day variation of insulin sensitivity in patients with type 1 diabetes: Role of gender and menstrual cycle, Diabet. Med. source
    • cites [15] Widom, 1992, Alteration in glucose metabolism during menstrual cycle in women with IDDM, Diabetes Care source
    • cites [16] Macdonald, 1990, Effect of phase of menstrual cycle on insulin sensitivity, peripheral blood flow and cardiovascular responses to hyperinsulinaemia in young women with type 1 diabetes, Diabet. Med. source
  • Findingcitation

    Two studies found unchanged glucose metrics across phases of the menstrual cycle in women with type 1 diabetes, checked by CGM or SMBG.

    “two studies [11,21] show unchanged glucose metrics across phases of the MC, checked by CGM or SMBG.”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [11] Lundman, 1994, Metabolic control, food intake and mood during the menstrual cycle in patients with insulin-dependent diabetes, Int. J. Nurs. Stud. source
    • cites [21] Levy, 2022, Insulin delivery and glucose variability throughout the menstrual cycle on closed loop control for women with type 1 diabetes, Diabetes Technol. Ther. source
  • Classified as probably not a substantial claim. 16
  • May combine two claims. 12
  • Not yet classified. 1

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    A number of variables and determinants (e.g., carbohydrate intake, physical activity, premenstrual syndrome symptoms, sleep quality and quantity) have to be considered when monitoring patients over a medium-to-long period.

    “the number of variables and determinants to be considered when monitoring patients over a medium-to-long period (i.e., carbohydrate intake, the frequency, duration and intensity of physical activity, premenstrual syndrome (PMS) symptoms and the quality and quantity of sleep) [8,9,10,11]”
    Quote in the paperNot a substantial claim1 of 4 sources checked
    • cites [8] Cawood, 1993, Perimenstrual symptoms in women with diabetes mellitus and the relationship to diabetic control, Diabet. Med. source
    • cites [9] Gamarra, 2016, Menstrual cyclicity, sleep efficiency and unplanned physical activity: Glycemic response in women suffering from type 1 diabetes mellitus, J. AMD

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [10] Tatulashvili, 2022, Ambulatory glucose profile according to different phases of the menstrual cycle in women living with type 1 diabetes, J. Clin. Endocrinol. Metab. source

      The Outcomes section (page unavailable) says the study collected information on dietary changes, physical activity, and premenstrual syndrome symptoms during menstrual cycles. The Strengths and Limitations section (page unavailable) calls for more detailed study of food intake and physical activity. Our copy does not specify carbohydrate intake, the frequency, duration or intensity of activity, or sleep quality and quantity, nor does it make a general recommendation about medium-to-long-term monitoring. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [11] Lundman, 1994, Metabolic control, food intake and mood during the menstrual cycle in patients with insulin-dependent diabetes, Int. J. Nurs. Stud. source

  • May combine two claims.

    Premisecitation

    Previous research has used various techniques to assess insulin sensitivity during the menstrual cycle, but most studies were performed in nondiabetic women and obtained different results with hyperglycaemic versus euglycaemic techniques.

    “Previous research has indeed used various techniques to assess IS during the MC such as the glucose tolerance test and the euglycaemic or hyperglycaemic clamp [25,26,27,28,29,30,31,32], but most of the studies have been performed in nondiabetic women and have obtained different results with the hyperglycemic versus the euglycemic technique.”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [25] Roy, 1971, Changes in oral glucose tolerance during normal menstrual cycle, J. Indian Med. Assoc.

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [26] Jarrett, 1968, Changes in oral glucose tolerance during the menstrual cycle, Br. Med. J. source
    • cites [27] Bonora, 1987, Influence of the menstrual cycle on glucose tolerance and insulin secretion, Am. J. Obstet. Gynecol. source

  • Classified as probably not a substantial claim.

    Findingcitation

    Some studies show that the glycaemic worsening in the luteal phase affects postprandial glucose.

    “Since, according to some studies, this worsening affects postprandial glucose [13,19,22]”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [13] Goldner, 2004, Cyclic changes in glycemia assessed by continuous glucose monitoring system during multiple complete menstrual cycles in women with type 1 diabetes, Diabetes Technol. Ther. source
    • cites [19] Herranz, 2016, Glycemic changes during menstrual cycles in women with type 1 diabetes, Med. Clin. source
    • cites [22] Barata, 2013, The effect of the menstrual cycle on glucose control in women with type 1 diabetes evaluated using a continuous glucose monitoring system, Diabetes Care source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation

    Other studies show that the glycaemic worsening in the luteal phase occurs mainly in fasting glucose due to accentuation of the dawn phenomenon caused by progesterone.

    “However, according to other studies, the worsening occurs mainly in fasting glucose due to the accentuation of the dawn phenomenon caused by progesterone [22,34]”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [22] Barata, 2013, The effect of the menstrual cycle on glucose control in women with type 1 diabetes evaluated using a continuous glucose monitoring system, Diabetes Care source

      The paper’s main text (page unavailable) reports higher luteal-phase glucose at fasting, but also after breakfast and lunch and before dinner; it does not establish that worsening occurs mainly while fasting. It reports higher progesterone in the luteal phase and suggests a possible hormonal effect, but does not identify a progesterone-caused accentuation of the dawn phenomenon. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [34] Jovanovic, 2004, Advances in diabetes for the millennium: Diabetes in women, MedGenMed

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingown data

    The included studies were published between 1990 and 2022, with sample sizes from 4 to 124 patients.

    “We included 14 studies published between 1990 and 2022, with sample sizes from 4 to 124 patients.”
    • Also stated in: § 3.2. Qualitative Analysis · plain
      “The 14 articles were published between 1990 and 2022 in scientific journals in the fields of diabetology-endocrinology and nursing care.”
    • Also stated in: § 3.2. Qualitative Analysis · plain
      “Overall, the sample size ranged from 4 to 124 patients.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingreasoning

    The phenotype of the glycaemic worsening found in the luteal phase is unclear.

    “Second, the phenotype of the glycaemic worsening found in the luteal phase is unclear.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    Three included studies measured levels of hormones potentially influencing differences in insulin sensitivity across menstrual cycle phases, including cortisol, norepinephrine, GH, testosterone, DHT and androstenedione.

    “As an additional factor of heterogeneity, three studies also measured the levels of some hormones potentially influencing the difference in IS found across the phases of the menstrual cycle, such as cortisol, norepinephrine, GH, testosterone, DHT and androstenedione.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    Insulin sensitivity refers to daytime, night-time or both in different studies.

    “Furthermore, IS refers to daytime, night-time or both in different studies.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    Five included articles considered other factors and collected data through wearable trackers, questionnaires or validated scales (Penn Daily Symptoms Rating Scale and Pittsburg Sleep Quality Index) on body temperature, weight, occasional medications, physical exercise, sleep quantity and quality, emotional state, psychosocial condition and premenstrual symptoms.

    “Finally, in five articles, other factors are considered and other data are collected through wearable trackers, questionnaires or validated scales (Penn Daily Symptoms Rating Scale and Pittsburg Sleep Quality Index): body temperature, weight, occasional medications, physical exercise, sleep quantity and quality, emotional state, psychosocial condition and premenstrual symptoms.”
    Quote in the paperNot a substantial claim

  • Not yet classified.

    Finding

    Two studies found no statistically significant differences in insulin sensitivity across phases of the menstrual cycle in women with type 1 diabetes, estimated by IGIT or euglycaemic clamp.

    “two studies [7,8,9,10,11,12,13,14,15,16] show the absence of SS differences in IS in the various phases of the MC, estimated by IGIT or the euglycaemic clamp.”
    Quote in the paperNot yet classified0 of 3 sources checked
    • cites [7] Moberg, 1995, Day-to-day variation of insulin sensitivity in patients with type 1 diabetes: Role of gender and menstrual cycle, Diabet. Med. source
    • cites [8] Cawood, 1993, Perimenstrual symptoms in women with diabetes mellitus and the relationship to diabetic control, Diabet. Med. source
    • cites [9] Gamarra, 2016, Menstrual cyclicity, sleep efficiency and unplanned physical activity: Glycemic response in women suffering from type 1 diabetes mellitus, J. AMD

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingreasoning

    The prevalence of the 'menstrual cycle phenomenon' among women with type 1 diabetes is unclear.

    “First, the prevalence of the “menstrual cycle phenomenon” among women with T1DM is unclear”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingreasoning

    The retrieved data did not allow the authors to perform a meta-analysis or achieve quantitative results.

    “The retrieved data did not allow us to perform a meta-analysis.”
    • Also stated in: § Abstract · plain
      “There is no conclusive evidence, and published data do not allow us to achieve quantitative results.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingown data

    The number of menstrual cycles observed ranged from 1 to 6.5 per patient (total 6 to 168).

    “The number of MCs observed ranged from 1 to 6.5/patient (total number from 6 to 168 MCs).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation

    It is unclear whether fluctuations of other hormones (such as GH, steroids and androgens) over the menstrual cycle are related to variability in glucose control.

    “Finally, it is still unclear whether fluctuations of other hormones (such as GH, steroids and androgens) over the MC are related to the variability in glucose control [13,16].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [13] Goldner, 2004, Cyclic changes in glycemia assessed by continuous glucose monitoring system during multiple complete menstrual cycles in women with type 1 diabetes, Diabetes Technol. Ther. source
    • cites [16] Macdonald, 1990, Effect of phase of menstrual cycle on insulin sensitivity, peripheral blood flow and cardiovascular responses to hyperinsulinaemia in young women with type 1 diabetes, Diabet. Med. source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    The systematic review was performed in accordance with the PRISMA statement.

    “The systematic review was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement [17].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [17] Moher, 2009, Preferred reporting items for systematic reviews and meta-analyses: The PRISMA statement, BMI

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given

    The literature was searched by two authors independently using PubMed/MEDLINE, Embase and Scopus, with the last search on 2 November 2022.

    “The literature was searched by two authors independently using PubMed/MEDLINE, Embase and Scopus (last search on 2 November 2022).”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductnone given

    Two investigators independently searched for papers, screened titles and abstracts, reviewed full texts and selected articles for inclusion, with discordances solved by mutual consensus.

    “Two investigators (EG and PT) independently searched for papers, screened the titles and abstracts of the retrieved articles, reviewed the full texts and selected articles for inclusion. Discordances were solved in a mutual consensus.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    Risk of bias in included studies was independently assessed by two authors according to the National Heart, Lung and Blood Institute Quality Assessment Tool for Observational Studies.

    “The risk of bias in included studies was independently assessed by the two authors according to the National Heart, Lung and Blood Institute Quality Assessment Tool for Observational Studies [18].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [18] (2022, November 16). Study Quality Assessment Tools | NHLBI, NIH, Available online: https://www.nhlbi.nih.gov/health-topics/study-quality-assessment-tools.

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    A subset of women with type 1 diabetes (but not all) experience a 'menstrual cycle phenomenon' that can hinder optimal glycaemic control and negatively impact quality of life.

    “Just as some (but not all) T1DM individuals experience a “dawn phenomenon” that requires insulin adjustment, a subset of T1DM women (but not all of them) experience a “menstrual cycle phenomenon” [23], which can represent an obstacle to the achievement of optimal glycaemic control and negatively impact patients’ quality of life.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [23] Trout, 2007, Mentrual cycle effects on insulin sensitivity in women with type 1 diabetes: A pilot study, Diabetes Technol. Ther. source

  • May combine two claims.

    Study design and conductcitation

    Glycaemic metrics were heterogeneous across included studies, with only a few studies using CGM metrics as recommended by international guidelines and often over a limited period of observation.

    “Third, glycaemic metrics were also heterogeneous, with only a few studies using CGM metrics as recommended by international guidelines [24] and often over a limited period of observation.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [24] Battelino, 2023, Continuous glucose monitoring and metrics for clinical trials: An international consensus statement, Lancet Diabetes Endocrinol. source

  • May combine two claims.

    Study design and conductown data

    Overall risk of bias in the included studies was high, especially concerning sample size, power analysis, timeframe, exposure definition and assessment, and potential confounding variables.

    “Overall, the risk of bias was high, especially concerning the sample size, analysis of the power of the sample, timeframe, exposure definition and assessment and potential confounding variables.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationcitation

    The euglycaemic range of nondiabetic subjects does not reflect the relatively hyperglycaemic state that characterizes T1DM patients and can impact glucose tolerance.

    “Therefore, applying their results to T1DM women requires much caution, as the euglycaemic range of nondiabetic subjects does not reflect the real relatively hyperglycaemic state that characterizes T1DM patients and can impact glucose tolerance [33].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [33] Ader, 1985, Importance of glucose per se to intravenous glucose tolerance. Comparison of the minimal-model prediction with direct measurements, Diabetes source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    The availability of new technologies has increased the possibility to optimize glycaemic control through tailoring of insulin treatment, resulting in a potential attenuation of menstrual-associated variability.

    “On the other hand, the availability of new technologies has increased the possibility to optimize glycaemic control through the tailoring of insulin treatment, resulting in a potential attenuation of menstrual-associated variability.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Estradiol may contribute to the increased risk of hyperglycaemia, and its lowering increases the risk of hypoglycaemia.

    “On the one hand, estradiol may contribute to the increased risk of hyperglycaemia, and its lowering increases the risk of hypoglycaemia [15].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [15] Widom, 1992, Alteration in glucose metabolism during menstrual cycle in women with IDDM, Diabetes Care source
24 of 24

  • The paper relies on this without support.

    In clinical practice, women with type 1 diabetes require therapy adjustment during different phases of the menstrual cycle because of incomplete glycaemic control.

    “To summarize, we face in clinical practice T1DM women requiring therapy adjustment during different phases of the MC because of incomplete glycaemic control, but we have no solid information about this phenomenon.”
1 of 1

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.

  • Nine hyperglycaemia studies are claimed, but only eight are cited

    Minor

    The citations across the listed hyperglycaemia measures identify eight distinct studies: 9, 10, 12, 14, 15, 19, 22 and 23. The text says nine studies showed this result.

  • Two insulin-sensitivity studies are described with ten citations

    Minor

    The statement says two studies found no statistically significant insulin-sensitivity differences, but its citation list contains ten distinct references. It also includes reference 8, which is not among the studies identified as included in the review.

2 of 2

Cites

Flagged first, then by citations

Research works printed but not linked: 1

  1. Gamarra, 2016, Menstrual cyclicity, sleep efficiency and unplanned physical activity: Glycemic response in women suffering from type 1 diabetes mellitus, J. AMD, 19, 105

Cited by

Sorted by citations

Related

Authors
Gamarra, E., & Trimboli, P.
Affiliations
Ente Ospedaliero Cantonale (CH)
Corresponding author
Gamarra, Elena
ORCID
Venue
Journal of Personalized Medicine
Publisher
MDPI AG
Published
2023-02-20
Volume
13
Issue
2
Pages
374
ISSN
2075-4426 (ISSN-L)
DOI
10.3390/jpm13020374
PMC
PMC9962060
OpenAlex
W4321457600
Semantic Scholar
1524e6719c25e8d73c6ae4691a388c8f7ff780e8
Cited by
29
References
39
Citations by year
2026: 16 · 2025: 7 · 2024: 5 · 2023: 1
FWCI
1.67
Type
journal article
Language
en
Open access
Licence
Locations
  • Journal of Personalized Medicine (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • PubMed Central (submittedVersion, cc-by)
Topics
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Diabetes Management and Research
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Diabetes, Cardiovascular Risks, and Lipoproteins
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Diabetes Management and Education
Keywords
menstrual cycle, type 1 diabetes, insulin sensitivity, glycemic control, luteal phase, hyperglycemia, menstrual cycle phases, hormonal evaluation, glycaemic outcomes

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