Society for Maternal-Fetal Medicine Consult Series #52: Diagnosis and management of fetal growth restriction

In the paper

“However, this finding was not confirmed in the Aspirin for Evidence-Based Preeclampsia Prevention (ASPRE) trial, which was primarily designed for preterm preeclampsia prevention.74,75”

What the sources say

• Disputed

  The Primary Outcome section reports significantly less preterm preeclampsia with aspirin than placebo (1.6% versus 4.3%; P = 0.004), contrary to the claim that the trial did not confirm an aspirin benefit. The Discussion confirms that preterm preeclampsia was the trial’s primary outcome; it notes no significant differences for other outcomes, but says the trial was not adequately powered for them. (LLM, conf=0.89)

  Checked by a reasoning model — may be wrong.

  cites [74] Rolnik, 2017, Aspirin versus Placebo in Pregnancies at High Risk for Preterm Preeclampsia, N Engl J Med sourceExperimental — accuracy not yet measured
• Supported

  In “Prevention of FGR: Aspirin and other antiplatelet agents,” the review reports that meta-analyses found a modest aspirin benefit for FGR and SGA. It then says the ASPRE trial was designed to prevent preterm preeclampsia and found unchanged SGA rates despite a reduction in preterm preeclampsia. Thus, the claim is supported when the finding refers to fetal growth outcomes, not preeclampsia. (LLM, conf=0.93)

  cites [75] Groom, 2018, The role of aspirin, heparin, and other interventions in the prevention and treatment of fetal growth restriction, Am J Obstet Gynecol source

In the paper

“The available evidence does not indicate improved accuracy of CPR over umbilical artery Doppler, and clinical trials are needed to evaluate the effectiveness of CPR in guiding clinical management, especially in late-onset FGR, before its use in routine surveillance of pregnancies with FGR can be recommended.139”

What the sources say

• Disputed

  The Results (Direct comparisons) and Discussion (Summary of main results) report that CPR was significantly more accurate than umbilical artery Doppler for composite adverse outcome and emergency delivery for fetal distress, though accuracy was similar for other outcomes. The Conclusion also says CPR can improve accuracy. The paper does call for clinical trials before using CPR to guide management, but that does not support the claim that the available evidence indicates no accuracy improvement. (LLM, conf=0.89)

  Checked by a reasoning model — may be wrong.

  cites [139] Vollgraff Heidweiller-Schreurs, 2018, Prognostic accuracy of cerebroplacental ratio and middle cerebral artery Doppler for adverse perinatal outcome: systematic review and meta-analysis, Ultrasound Obstet Gynecol sourceExperimental — accuracy not yet measured

In the paper

“It also can contribute to cardiac remodeling, leading to cardiovascular dysfunction that can persist into childhood and adolescence.13,14”

What the sources say

• Partly supported

  The Introduction and Discussion report that intrauterine growth restriction is associated with fetal cardiovascular remodeling and dysfunction, and the study found that the pattern persisted at six months. The Introduction also discusses cardiovascular changes in children and young adults, but the Strengths and limitations section says persistence of this study’s findings in the long term remains to be established. It therefore does not establish that the cardiac dysfunction persists into adolescence. (LLM, conf=0.86)

  cites [13] Cruz-Lemini, 2016, Fetal cardiovascular remodeling persists at 6 months in infants with intrauterine growth restriction, Ultrasound Obstet Gynecol sourceExperimental — accuracy not yet measured
• ?Not checked — no full text of the sourcecites [14] Crispi, 2010, Fetal growth restriction results in remodeled and less efficient hearts in children, Circulation source

In the paper

“Perinatal outcomes are largely dependent on the severity of FGR, with the worst outcomes noted in fetuses with estimated fetal weights (EFWs) at less than the third percentile or in association with fetal Doppler abnormalities.5,10”

What the sources say

• Supported

  The Background states that outcomes in growth-restricted fetuses depend largely on severity, with those below the 3rd centile and/or with abnormal umbilical artery Doppler measurements at greatest risk. The Discussion likewise identifies EFW below the 3rd centile and/or abnormal umbilical artery Doppler as markers of greater risk of poor perinatal outcome. (LLM, conf=0.94)

  cites [5] Unterscheider, 2014, Fetal growth restriction and the risk of perinatal mortality-case studies from the multicentre PORTO study, BMC Pregnancy Childbirth source
• ?Not checked — no full text of the sourcecites [10] Savchev, 2012, Estimated weight centile as a predictor of perinatal outcome in small-for-gestational-age pregnancies with normal fetal and maternal Doppler indices, Ultrasound Obstet Gynecol source

In the paper

“Fetal growth restriction (FGR) can result from a variety of maternal, fetal, and placental conditions. 1”

What the sources say

• Supported

  The Tables 1–6 passage (page not provided) identifies fetal structural or genetic defects and placental insufficiency as causes of FGR. It also describes maternal and fetal blood-flow changes and placental changes that can contribute to insufficiency, supporting the paraphrase. (LLM, conf=0.92)

  cites [1] Swanson, 2015, Animal models of fetal growth restriction: Considerations for translational medicine, Placenta source

In the paper

“It has been associated with metabolic programming that increases the risk of future development of metabolic syndrome and consequent cardiovascular and endocrine diseases.11,12”

What the sources say

• ?Not checked — no full text of the sourcecites [11] Crispi, 2012, Cardiovascular programming in children born small for gestational age and relationship with prenatal signs of severity, Am J Obstet Gynecol source
• Partly supported

  The Abstract states that fetal growth restriction causes metabolic programming that may increase the risk of metabolic syndrome and, consequently, adult cardiovascular morbidity. The Fetal Programming of Adult Cardiovascular Disease section also discusses diabetes as a metabolic disease, but does not say that metabolic syndrome leads to endocrine diseases. The claim therefore adds an unsupported consequence and is more certain than the paper’s qualified statement. (LLM, conf=0.88)

  cites [12] Crispi, 2018, Long-term cardiovascular consequences of fetal growth restriction: biology, clinical implications, and opportunities for prevention of adult disease, Am J Obstet Gynecol sourceExperimental — accuracy not yet measured

In the paper

“However, this approach requires multiple ultrasound examinations, and prospective studies fail to demonstrate the superiority of this approach in improving clinical outcomes.35”

What the sources say

• Partly supported

  The Conclusion (page unavailable) says that estimating a fetal growth trajectory requires at least two measurements and that one-time measurement remains standard clinical practice. It does not report that prospective studies tested the trajectory approach against another approach or failed to show superior clinical outcomes. (LLM, conf=0.82)

  cites [35] Grantz, 2018, Fetal growth standards: the NICHD fetal growth study approach in context with INTERGROWTH-21st and the World Health Organization Multicentre Growth Reference Study, Am J Obstet Gynecol sourceExperimental — accuracy not yet measured

In the paper

“Although the primary underlying mechanisms for FGR are varied, they often share the same final common pathway of suboptimal fetal nutrition and uteroplacental perfusion.1,2”

What the sources say

• Supported

  The Tables 1–6 section describes placental insufficiency as the primary cause of FGR apart from fetal structural or genetic defects. It defines this as inadequate fetal acquisition of nutrients and oxygen, arising through varied factors that include altered blood flow and reduced nutrient transport, consistent with the citing sentence’s broad paraphrase. (LLM, conf=0.85)

  cites [1] Swanson, 2015, Animal models of fetal growth restriction: Considerations for translational medicine, Placenta source
• Partly supported

  Section 2.1 (Causes) describes varied fetal, maternal, environmental, and placental causes of FGR and says uteroplacental hypoperfusion can impair fetal growth. Section 2.2 (Placental Dysfunction) links inadequate placentation to FGR and describes the placenta’s role in nutrient absorption. The paper does not establish that these varied causes often converge on a shared final pathway involving both suboptimal fetal nutrition and uteroplacental perfusion. (LLM, conf=0.78)

  cites [2] Bamfo, 2011, Diagnosis and management of fetal growth restriction, J Pregnancy sourceExperimental — accuracy not yet measured

In the paper

“Of fetuses diagnosed with FGR, approximately 18%e22% will be constitutionally small but healthy at birth with a normal outcome.24”

What the sources say

• Partly supported

  The Introduction says 18–22% of babies classified as small for gestational age (SGA) are constitutionally small but healthy. The Expert Reviews section says reclassified babies have perinatal mortality similar to normally grown babies. The figure applies to SGA infants, not fetuses diagnosed with FGR, and similar mortality does not establish a normal outcome in every respect. (LLM, conf=0.88)

  cites [24] McCowan, 2018, Evidence-based national guidelines for the management of suspected fetal growth restriction: comparison, consensus, and controversy, Am J Obstet Gynecol sourceExperimental — accuracy not yet measured

In the paper

“A review of national guidelines for the diagnostic criteria for FGR from 6 countries (United States, United Kingdom, France, Ireland, Canada, and New Zealand) reveals a broad consensus on this definition of FGR.24”

What the sources say

• Supported

  The Results identify national guidelines from the six named countries. The Comment states that all guidelines recommended estimated fetal weight below the 10th centile as an appropriate definition of FGR, while noting that some require additional parameters to confirm pathological growth restriction. (LLM, conf=0.91)

  cites [24] McCowan, 2018, Evidence-based national guidelines for the management of suspected fetal growth restriction: comparison, consensus, and controversy, Am J Obstet Gynecol source

In the paper

“The single most important prognostic factor in preterm fetuses with growth restriction is the gestational age at delivery.80,83”

What the sources say

• Partly supported

  The Results (page not available) say gestational age at delivery was strongly related to infant outcome, and babies with poor outcomes were delivered earlier. They do not identify it as the single most important prognostic factor; the Discussion instead calls maternal hypertension the major determinant of adverse outcome. (LLM, conf=0.88)

  cites [80] Lees, 2013, Perinatal morbidity and mortality in early-onset fetal growth restriction: cohort outcomes of the trial of randomized umbilical and fetal flow in Europe (TRUFFLE), Ultrasound Obstet Gynecol sourceExperimental — accuracy not yet measured
• Partly supported

  The Results report that gestational age was the most significant determinant of neonatal survival until 26 6/7 weeks. The claim is broader than that finding: the paper describes gestational age as a significant contributor to major morbidity until 29 2/7 weeks, and the Discussion identifies ductus venosus abnormality as an important predictor of neonatal complications beyond 27 weeks. Page numbers were not provided in our copy. (LLM, conf=0.85)

  cites [83] Baschat, 2007, Predictors of neonatal outcome in early-onset placental dysfunction, Obstet Gynecol sourceExperimental — accuracy not yet measured

In the paper

“The presence of maternal hypertension was one of the most important independent determinants of poor outcomes.16,80”

What the sources say

• ?Not checked — no full text of the sourcecites [16] Lees, 2015, 2 year neurodevelopmental and intermediate perinatal outcomes in infants with very preterm fetal growth restriction (TRUFFLE): a randomised trial, Lancet source
• Supported

  The Results identify gestational hypertensive morbidity at study entry as one of the most important independent determinants of the composite poor outcome of death or severe morbidity (OR 1.70; 95% CI 1.11–2.62). The Discussion also calls maternal hypertension a major determinant of adverse outcome. (LLM, conf=0.94)

  cites [80] Lees, 2013, Perinatal morbidity and mortality in early-onset fetal growth restriction: cohort outcomes of the trial of randomized umbilical and fetal flow in Europe (TRUFFLE), Ultrasound Obstet Gynecol source

In the paper

“We recommend that a detailed obstetrical ultrasound examination (current procedural terminology code 76811) be performed with early-onset FGR because up to 20% of cases are associated with fetal or chromosomal abnormalities 2,3,84,85 (GRADE 1B).”

What the sources say

• Partly supported

  Section 2.1 (Causes; page not provided) identifies fetal malformations and aneuploidy as causes of FGR. It does not give an up-to-20% figure for fetal or chromosomal abnormalities in early-onset FGR. Its separate figure of over 20% concerns confined placental mosaicism in idiopathic FGR. (LLM, conf=0.85)

  cites [2] Bamfo, 2011, Diagnosis and management of fetal growth restriction, J Pregnancy sourceExperimental — accuracy not yet measured
• ?Not checked — no full text of the sourcecites [3] Resnik, 2002, Intrauterine growth restriction, Obstet Gynecol source
• ?Not checked — no full text of the sourcecites [84] Hendrix, 2008, Non-placental causes of intrauterine growth restriction, Semin Perinatol source
• ?Not checked — no full text of the sourcecites [85] Maulik, 2006, Fetal growth restriction: the etiology, Clin Obstet Gynecol source

In the paper

“In early-onset FGR, the pattern of Doppler deterioration progresses from abnormalities in the umbilical arteries and the ductus venosus to abnormal biophysical parameters.55,56”

What the sources say

• Supported

  The Ductus venosus Doppler section describes early umbilical-artery changes followed by later ductus venosus abnormalities. It also reports that ductus venosus Doppler is abnormal 48–72 hours before the biophysical profile in about 90% of cases, supporting the stated progression while not making it universal. (LLM, conf=0.91)

  cites [55] Dall'Asta, 2017, Early onset fetal growth restriction, Matern Health Neonatol Perinatol source
• ?Not checked — no full text of the sourcecites [56] Figueras, 2018, Diagnosis and surveillance of late-onset fetal growth restriction, Am J Obstet Gynecol source

In the paper

“Furthermore, the use of low-molecularweight heparin has not been shown to reduce the risk of recurrent placenta-mediated pregnancy complications in at-risk women.75,77,78”

What the sources say

• Supported

  The Clinical studies of LMWH section explicitly concludes that LMWH does not reduce the risk of recurrent placenta-mediated pregnancy complications in at-risk women. It acknowledges that any protective effect, if present, may be modest or limited to subgroups, which is consistent with the claim's wording, ‘has not been shown.’ (LLM, conf=0.95)

  cites [75] Groom, 2018, The role of aspirin, heparin, and other interventions in the prevention and treatment of fetal growth restriction, Am J Obstet Gynecol source
• ?Not checked — no full text of the sourcecites [77] Haddad, 2016, Enoxaparin and Aspirin Compared With Aspirin Alone to Prevent Placenta-Mediated Pregnancy Complications: A Randomized Controlled Trial, Obstet Gynecol source
• Supported

  The Introduction states that recent meta-analyses failed to conclusively demonstrate a reduction in placenta-mediated complications in subsequent pregnancies among women deemed high risk. The Comment also reports that the EPPI trial found no beneficial effect of enoxaparin on recurrence of preeclampsia and small-for-gestational-age birth. Page numbers were not provided in our copy. (LLM, conf=0.93)

  cites [78] Groom, 2017, Enoxaparin for the prevention of preeclampsia and intrauterine growth restriction in women with a history: a randomized trial, Am J Obstet Gynecol source

In the paper

“Furthermore, the presence of a standardized protocol for diagnosis and management appears to be associated with more favorable outcomes, as evidenced in the better-than-expected perinatal morbidity and mortality in the Trial of Randomized Umbilical and Fetal Flow in Europe (TRUFFLE).80”

What the sources say

• Supported

  The Discussion (page not provided) says TRUFFLE used a consensus antenatal monitoring and delivery protocol and describes its perinatal outcomes as somewhat better than expected. It suggests that improvements in antenatal monitoring, alongside developments in neonatal care, likely contributed; the citing sentence’s cautious ‘appears to be associated’ is consistent with that account. (LLM, conf=0.88)

  cites [80] Lees, 2013, Perinatal morbidity and mortality in early-onset fetal growth restriction: cohort outcomes of the trial of randomized umbilical and fetal flow in Europe (TRUFFLE), Ultrasound Obstet Gynecol source

In the paper

“A large longitudinal cohort study on FGR showed an increase of 1%e2% in intact survival for every additional day spent in utero up until 32 weeks of gestation.83”

What the sources say

• Partly supported

  The Results report that this large study of growth-restricted fetuses found neonatal survival gains of about 2% per day in utero from 24 to 27 weeks and 1% thereafter; they also report increasing intact survival through 32 weeks. The paper does not assign those per-day percentages to intact survival, as the citing sentence does. (LLM, conf=0.88)

  cites [83] Baschat, 2007, Predictors of neonatal outcome in early-onset placental dysfunction, Obstet Gynecol sourceExperimental — accuracy not yet measured

In the paper

“At present, there is no evidence that therapeutic interventions, including sildenafil to augment uteroplacental perfusion through vasodilation, improve placental perfusion and outcome in pregnancies with FGR.75,79”

What the sources say

• Partly supported

  The Implications for practice section (page unavailable) says there are no proven treatments that improve fetal growth or outcome after FGR is diagnosed. But the clinical-studies discussion (page unavailable) reports reduced umbilical artery resistance after a single sildenafil dose in FGR pregnancies, evidence of an effect on fetoplacental circulation. Thus the claim captures the lack of a proven outcome benefit but overstates the absence of evidence for a perfusion-related effect. (LLM, conf=0.82)

  cites [75] Groom, 2018, The role of aspirin, heparin, and other interventions in the prevention and treatment of fetal growth restriction, Am J Obstet Gynecol sourceExperimental — accuracy not yet measured
• ?Not checked — no full text of the sourcecites [79] Groom, 2019, STRIDER NZAus: a multicentre randomised controlled trial of sildenafil therapy in early-onset fetal growth restriction, Bjog source

In the paper

“Similarly, in a secondary analysis of data from TRUFFLE, middle cerebral artery Doppler did not add useful information beyond umbilical artery and ductus venosus Doppler assessments for optimizing the timing of delivery.131”

What the sources say

• Partly supported

  The Abstract’s Study Design identifies this as a secondary analysis of TRUFFLE, and its Conclusion says middle cerebral artery Doppler is unlikely to help optimize delivery timing in fetal growth restriction before 32 weeks. However, the Conclusion describes a monitoring protocol based on ductus venosus Doppler and cardiotocography, not a comparison against combined umbilical artery and ductus venosus Doppler assessments. (LLM, conf=0.84)

  cites [131] Stampalija, 2017, Is middle cerebral artery Doppler related to neonatal and 2-year infant outcome in early fetal growth restriction?, Am J Obstet Gynecol sourceExperimental — accuracy not yet measured

In the paper

“Evidence suggests that umbilical artery Doppler does not reliably predict adverse pregnancy outcome in late-onset FGR.101”

What the sources say

• Supported

  The Introduction states that most adverse outcomes attributable to late-onset growth restriction occur in fetuses with normal umbilical artery (UA) Doppler, and explicitly says UA Doppler cannot be relied on to identify those at risk. The Discussion likewise warns that a normal UA result may give false reassurance. This supports the claim about its limited predictive reliability in late-onset FGR. (LLM, conf=0.93)

  cites [101] Oros, 2011, Longitudinal changes in uterine, umbilical and fetal cerebral Doppler indices in late-onset small-for-gestational age fetuses, Ultrasound Obstet Gynecol source

In the paper

“These risks of stillbirth are higher than the risk of infant mortality or severe morbidity at 33e34 weeks for AEDV and at 30e32 weeks for REDV as reported in TRUFFLE.80”

What the sources say

• Partly supported

  Table 4 (section labeled Discussion; page unavailable) reports neonatal death and severe morbidity by gestational age at delivery, providing TRUFFLE outcomes relevant to the comparison. But it does not separate AEDV from REDV or compare those groups’ stillbirth risks with infant outcomes at the stated weeks; that comparison is not established by this source. (LLM, conf=0.87)

  cites [80] Lees, 2013, Perinatal morbidity and mortality in early-onset fetal growth restriction: cohort outcomes of the trial of randomized umbilical and fetal flow in Europe (TRUFFLE), Ultrasound Obstet Gynecol sourceExperimental — accuracy not yet measured

In the paper

“As such, it is an essential component of fetal surveillance in FGR.96,97”

What the sources say

• ?Not checked — no full text of the sourcecites [96] McCowan, 2000, A pilot randomized controlled trial of two regimens of fetal surveillance for small-for-gestational-age fetuses with normal results of umbilical artery doppler velocimetry, Am J Obstet Gynecol source
• Partly supported

  The Authors’ Conclusions (Implications for practice; page unavailable) say umbilical artery Doppler improves perinatal outcomes in high-risk pregnancies at risk of placental insufficiency and identify small-for-date fetuses as obvious candidates. That supports its use in fetal growth restriction, but the review does not establish that it is essential for surveillance in every FGR pregnancy. (LLM, conf=0.82)

  cites [97] Alfirevic, 2017, Fetal and umbilical Doppler ultrasound in high-risk pregnancies, Cochrane Database Syst Rev sourceExperimental — accuracy not yet measured

In the paper

“After 32 weeks of gestation, abnormal CTG findings will almost invariably precede Doppler abnormalities of the ductus venosus.111”

What the sources say

• ?Could not verify

  The Discussion (page unavailable) describes cardiotocography as complementary to Doppler surveillance, but does not say which finding occurs first. A search for “32 weeks” found no gestational-age-specific comparison, so our copy does not verify the claimed sequence after 32 weeks. (LLM, conf=0.75)

  cites [111] Baschat, 2003, Qualitative venous Doppler waveform analysis improves prediction of critical perinatal outcomes in premature growth-restricted fetuses, Ultrasound Obstet Gynecol sourceExperimental — accuracy not yet measured

In the paper

“In contrast, a systematic review of 5 trials found no evidence of maternal or neonatal benefit from the routine use of umbilical artery Doppler in low-risk pregnancies.98”

What the sources say

• Supported

  The Discussion (Summary of main results) says the review included five studies and found no group differences in its primary outcomes of perinatal death and neonatal morbidity. The Authors’ Conclusions (Implications for practice) say the data do not provide robust evidence that routine umbilical artery Doppler in low-risk or unselected pregnancies benefits mother or baby. (LLM, conf=0.93)

  cites [98] Alfirevic, 2015, Fetal and umbilical Doppler ultrasound in normal pregnancy, Cochrane Database Syst Rev source

In the paper

“A prospective observational study of the progression of Doppler abnormalities in FGR suggests that rapid progression, if it is going to occur, is typically noted within the first 2 weeks after diagnosis.24,108”

What the sources say

• ?Could not verify

  The Results discuss surveillance after FGR diagnosis, and the Conclusions table lists Doppler monitoring intervals. Neither reports a prospective observational study finding that rapid Doppler deterioration typically appears within the first two weeks after diagnosis. Searches for that study and the two-week progression claim found no supporting passage in our copy. (LLM, conf=0.73)

  cites [24] McCowan, 2018, Evidence-based national guidelines for the management of suspected fetal growth restriction: comparison, consensus, and controversy, Am J Obstet Gynecol sourceExperimental — accuracy not yet measured
• Supported

  The Discussion says that after the initial 14 days following IUGR diagnosis, rapidly progressive severe disease will have become evident through worsening Doppler findings. This supports the claim's qualified statement about when rapid progression is typically noted. (LLM, conf=0.93)

  cites [108] Turan, 2008, Progression of Doppler abnormalities in intrauterine growth restriction, Ultrasound Obstet Gynecol source

In the paper

“There are currently no randomized trials with adequate sample size to inform recommendations regarding the optimal frequency of umbilical artery Doppler for FGR surveillance.107”

What the sources say

• Supported

  The Discussion (page not provided) says the sole included trial was a pilot, that a much larger study is needed, and that there is almost no evidence for an optimal surveillance method. The Interventions and Participants sections (pages not provided) show that the 167-person trial compared surveillance frequencies and included umbilical artery Doppler, supporting the claim that it could not establish the optimal Doppler frequency. (LLM, conf=0.87)

  cites [107] Grivell, 2012, Regimens of fetal surveillance for impaired fetal growth, Cochrane Database Syst Rev source

In the paper

“In TRUFFLE, delivery decisions guided by ductus venosus Doppler findings only accounted for about 11% of pregnancies allocated to the late ductus venosus findings group because most delivered due to other fetal or maternal indications.115,120,121”

What the sources say

• Partly supported

  The Introduction says that only a proportion of fetuses allocated to delivery for ductus venosus changes were delivered on that criterion; the majority were delivered under safety-net criteria. It does not give the claimed 11% figure for the late ductus venosus group or specify that the other deliveries were due to fetal or maternal indications. (LLM, conf=0.85)

  cites [115] Ganzevoort, 2017, How to monitor pregnancies complicated by fetal growth restriction and delivery before 32 weeks: post-hoc analysis of TRUFFLE study, Ultrasound Obstet Gynecol sourceExperimental — accuracy not yet measured
• Partly supported

  The section on deliveries for reasons other than abnormal DV Doppler (p. 4) says many women delivered for other reasons, including maternal complications and fetal distress. The section on neurological outcome (p. 4) also says that, across the two DV groups, twice as many fetuses delivered under CTG safety-net criteria as for DV changes. Neither passage gives 11% as the proportion of the late-DV group delivered because of DV findings; the reported 11% figures refer to other indications across the trial. (LLM, conf=0.88)

  cites [120] Bilardo, 2017, Severe fetal growth restriction at 26-32 weeks: key messages from the TRUFFLE study, Ultrasound Obstet Gynecol sourceExperimental — accuracy not yet measured
• Partly supported

  The Results report that 10% of cases in the late ductus venosus (DV-no-A) group were delivered for the allocated Doppler finding, consistent with 'about 11%.' But they say more than 50% were delivered because of safety-net criteria and almost 40% for other fetal or maternal indications. The claim incorrectly makes the latter the majority reason. (LLM, conf=0.92)

  cites [121] Visser, 2017, Fetal monitoring indications for delivery and 2-year outcome in 310 infants with fetal growth restriction delivered before 32 weeks' gestation in the TRUFFLE study, Ultrasound Obstet Gynecol sourceExperimental — accuracy not yet measured

In the paper

“However, uterine artery Doppler has limited diagnostic accuracy and clinical utility in predicting FGR, SGA birth, and perinatal mortality.148,149”

What the sources say

• ?Not checked — no full text of the sourcecites [148] Chien, 2000, How useful is uterine artery Doppler flow velocimetry in the prediction of pre-eclampsia, intrauterine growth retardation and perinatal death? An overview, Bjog source
• Partly supported

  The Comment reports a systematic review finding limited diagnostic accuracy for fetal growth restriction and perinatal death. It also reports low predictive and clinical utility for SGA and stillbirth in this study’s cohort of unselected nulliparous women screened in the early second trimester. The claim omits that population and timing limitation and extends the clinical-utility finding to FGR and perinatal mortality, which this study did not directly assess as such. (LLM, conf=0.84)

  cites [149] Parry, 2017, Role of early second-trimester uterine artery Doppler screening to predict small-for-gestational-age babies in nulliparous women, Am J Obstet Gynecol sourceExperimental — accuracy not yet measured

In the paper

“a normal CTG in pregnancies with FGR is more likely to be associated with a normal perinatal outcome”

What the sources say

• ?Could not verify

  The Results (page not available) report that 80% of infants delivered because of CTG abnormalities were normal at follow-up. Our copy does not compare outcomes after normal versus abnormal CTG, so it does not establish the claimed association; searches for normal CTG and outcomes found no such comparison. (LLM, conf=0.70)

  cites [121] Visser, 2017, Fetal monitoring indications for delivery and 2-year outcome in 310 infants with fetal growth restriction delivered before 32 weeks' gestation in the TRUFFLE study, Ultrasound Obstet Gynecol sourceExperimental — accuracy not yet measured

In the paper

“the presence of spontaneous repetitive late decelerations is accepted as an indication for delivery in viable pregnancies with FGR, irrespective of Doppler findings”

What the sources say

• Partly supported

  The Methods describe recurrent fetal-heart-rate decelerations as a delivery safety-net criterion in all three monitoring groups, including the groups monitored by ductus venosus Doppler. The paper does not specify that these were *late* decelerations, and its study population was pregnancies with very preterm fetal growth restriction at 26–32 weeks, not viable FGR pregnancies generally. The cited copy provides no page number for the Methods passage. (LLM, conf=0.85)

  cites [121] Visser, 2017, Fetal monitoring indications for delivery and 2-year outcome in 310 infants with fetal growth restriction delivered before 32 weeks' gestation in the TRUFFLE study, Ultrasound Obstet Gynecol sourceExperimental — accuracy not yet measured

In the paper

“In early-onset FGR associated with abnormal Doppler studies, neonatal survival increased from 13% at 24 weeks to 43% at 25 weeks and 58%-76% at 26 weeks of gestation.”

What the sources say

• Supported

  The “Prognosis of IUGR Infants Born before 31 Weeks of Gestation” section reports exactly these neonatal survival rates at 24, 25, and 26 weeks. The same section describes the underlying studies as using small-for-gestational-age status with abnormal umbilical-artery Doppler waveforms to identify fetal growth restriction. (LLM, conf=0.95)

  cites [159] Visser, 2014, Fetal growth restriction at the limits of viability, Fetal Diagn Ther source

In the paper

“A Cochrane review concluded that available evidence from randomized controlled trials does not support the use of BPP as a test of fetal well-being in high-risk pregnancies.153,154”

What the sources say

• Supported

  The Main results and Authors’ conclusions state that evidence from randomised trials does not support BPP as a test of fetal wellbeing in high-risk pregnancies. This matches the claim. (LLM, conf=0.95)

  cites [153] Lalor, 2008, Biophysical profile for fetal assessment in high risk pregnancies, Cochrane Database Syst Rev source
• Partly supported

  The COMMENT and SMFM Papers sections conclude that BPP alone is unreliable for predicting fetal well-being in severely preterm, growth-restricted fetuses. The paper does not report a Cochrane review or a conclusion from randomized controlled trials, and its findings do not cover high-risk pregnancies generally. Page numbers are unavailable in our copy. (LLM, conf=0.85)

  cites [154] Kaur, 2008, Biophysical profile in the treatment of intrauterine growth-restricted fetuses who weigh <1000 g, Am J Obstet Gynecol sourceExperimental — accuracy not yet measured

In the paper

“National guidelines from 4 countries recommend cesarean delivery when FGR is complicated by AEDV/REDV of the umbilical artery.24”

What the sources say

• Supported

  The Results state that, for preterm FGR with absent or reversed end-diastolic velocity, four of six guidelines specify cesarean delivery. The guideline tables also list cesarean delivery for AEDV and REDV in four countries. (LLM, conf=0.94)

  cites [24] McCowan, 2018, Evidence-based national guidelines for the management of suspected fetal growth restriction: comparison, consensus, and controversy, Am J Obstet Gynecol source

In the paper

“Observational studies have indicated that an abnormal biophysical profile (BPP) is a late manifestation of placental disease that appears to become abnormal 48e72 hours after ductus venosus Doppler abnormalities in 90% of cases.152”

What the sources say

• Partly supported

  The Results (p. 4) and Discussion (p. 6) support that Doppler deterioration, including changes in the ductus venosus, generally precedes a late decline in biophysical profile score. They do not support the claimed 48–72-hour interval in 90% of cases: the Results report a median of four days between accelerating ductus venosus indices and score decline, while the Abstract (p. 1) says Doppler deterioration was complete 24 hours before decline in 70.5% of cases and was simultaneous in 25%. (LLM, conf=0.90)

  cites [152] Baschat, 2001, The sequence of changes in Doppler and biophysical parameters as severe fetal growth restriction worsens, Ultrasound Obstet Gynecol sourceExperimental — accuracy not yet measured

In the paper

“Although both the NICHD and WHO studies identified racial/ethnic differences in fetal growth, evidence to date indicates that the use of these new formulas in clinical practice does not improve the detection and outcome of FGR.51e53”

What the sources say

• ?Not matched

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

  cites 51e53

In the paper

“In some studies, the use of customized growth standards has been shown to improve the ability to distinguish growthrestricted fetuses from constitutionally small fetuses.45e47”

What the sources say

• ?Not matched

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

  cites 45e47

In the paper

“Evidence supports the use of AC as a diagnostic criterion for FGR.”

What the sources say

• ?Not checked — no full text of the sourcecites [31] David, 1996, Receiver-operator characteristic curves for the ultrasonographic prediction of small-for-gestational-age fetuses in low-risk pregnancies, Am J Obstet Gynecol source
• ?Not checked — no full text of the sourcecites [32] Blue, 2017, Abdominal Circumference Alone versus Estimated Fetal Weight after 24 Weeks to Predict Small or Large for Gestational Age at Birth: A Meta-Analysis, Am J Perinatol source
• ?Not checked — no full text of the sourcecites [33] Caradeux, 2019, Diagnostic performance of third-trimester ultrasound for the prediction of late-onset fetal growth restriction: a systematic review and meta-analysis, Am J Obstet Gynecol source

In the paper

“For birthweights in the range of 1000e4500 g, formulas based on 3 or 4 fetal biometric indices were significantly more accurate in estimating fetal weights than formulas based on 1 or 2 indices.39”

What the sources say

• ?Not checked — no full text of the sourcecites [39] Melamed, 2009, Sonographic fetal weight estimation: which model should be used?, J Ultrasound Med source

In the paper

“However, there is significant variation in the diagnostic criteria used for FGR.”

What the sources say

• ?Not checked — no full text of the sourcecites [28] Gordijn, 2016, Consensus definition of fetal growth restriction: a Delphi procedure, Ultrasound Obstet Gynecol source

In the paper

“In a preterm population in France, the INTER-GROWTH-21st formula was associated with a higher mean percentage error and a higher underestimation of birthweight at >28 weeks of gestation when compared with Hadlock.”

What the sources say

• ?Not checked — no full text of the sourcecites [53] Monier, 2018, Comparison of the Hadlock and INTERGROWTH formulas for calculating estimated fetal weight in a preterm population in France, Am J Obstet Gynecol source

In the paper

“In a prospective study in 1000 low-risk pregnancies, an AC of less than the 10th percentile was found to have diagnostic accuracy similar to EFW less than the 10th percentile for the prediction of SGA. 31”

What the sources say

• ?Not checked — no full text of the sourcecites [31] David, 1996, Receiver-operator characteristic curves for the ultrasonographic prediction of small-for-gestational-age fetuses in low-risk pregnancies, Am J Obstet Gynecol source

In the paper

“Therefore, an EFW below the third percentile has been found to represent a more severe form of FGR.”

In the paper

“As early as 14 weeks of gestation, low impedance of the fetal placental circulation permits continuous forward flow in the umbilical artery throughout the cardiac cycle.95”

What the sources say

• ?Not matched

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

  cites [95] Trudinger, 1992, Doppler ultrasonography and fetal well-being

In the paper

“In a cohort of 656 pregnancies with FGR, a gestational age of 32 weeks at diagnosis was identified as the optimal cutoff to maximize the differences in associated comorbidities and pregnancy outcomes between early-and late-onset FGR.54”

What the sources say

• ?Not checked — no full text of the sourcecites [54] Savchev, 2014, Evaluation of an optimal gestational age cut-off for the definition of early- and late-onset fetal growth restriction, Fetal Diagn Ther source

In the paper

“Furthermore, HC/AC was not found to be an independent predictor of adverse pregnancy outcomes.67”

What the sources say

• ?Not checked — no full text of the sourcecites [67] David, 1995, The head-to-abdomen circumference ratio: a reappraisal, Ultrasound Obstet Gynecol source

In the paper

“More recent studies have evaluated the role of CMA in fetuses with early-onset growth restriction and no structural malformations; such studies have identified a 4%e10% incremental yield of CMA over karyotype.88e90”

What the sources say

• ?Not matched

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

  cites 88e90

In the paper

“Fetuses classified as growth restricted by Hadlock, but not by the NICHD growth standard, had significantly higher composite morbidity than fetuses of normal growth.51”

What the sources say

• ?Not checked — no full text of the sourcecites [51] Blue, 2018, Comparing the Hadlock fetal growth standard to the Eunice Kennedy Shriver National Institute of Child Health and Human Development racial/ethnic standard for the prediction of neonatal morbidity and small for gestational age, Am J Obstet Gynecol source

In the paper

“An EFW below the third percentile has also been associated with an increased risk of adverse perinatal outcome irrespective of umbilical and middle cerebral artery Doppler indices.10”

What the sources say

• ?Not checked — no full text of the sourcecites [10] Savchev, 2012, Estimated weight centile as a predictor of perinatal outcome in small-for-gestational-age pregnancies with normal fetal and maternal Doppler indices, Ultrasound Obstet Gynecol source

In the paper

“The presence of abnormal umbilical artery Doppler indices has been found to predict adverse perinatal outcomes.62”

What the sources say

• ?Not checked — no full text of the sourcecites [62] Unterscheider, 2013, Predictable progressive Doppler deterioration in IUGR: does it really exist?, Am J Obstet Gynecol source

In the paper

“In another prospective cohort study of 48 pregnancies with FGR, 1 newborn (2.1%) was diagnosed with congenital CMV.92”

What the sources say

• ?Not checked — no full text of the sourcecites [92] Tsuge, 2019, Prospective Cohort Study of Congenital Cytomegalovirus Infection during Pregnancy with Fetal Growth Restriction: Serologic Analysis and Placental Pathology, J Pediatr source

In the paper

“Two (0.6%) of the fetuses with congenital CMV had no ultrasonographic findings other than FGR.91”

What the sources say

• ?Not checked — no full text of the sourcecites [91] Yamamoto, 2013, Significance of maternal screening for toxoplasmosis, rubella, cytomegalovirus and herpes simplex virus infection in cases of fetal growth restriction, J Obstet Gynaecol Res source

In the paper

“More recently, growth and developmental delay have been evaluated from birth to the age of 4 years and shown to be similar in symmetric and asymmetric growth-restricted preterm newborns.66”

What the sources say

• ?Not checked — no full text of the sourcecites [66] Bocca-Tjeertes, 2014, Symmetrical and asymmetrical growth restriction in preterm-born children, Pediatrics source

In the paper

“Although chromosome abnormalities are more frequent in pregnancies with structural anomalies and FGR, in a systematic review that included fetuses with no structural malformations, the mean rate of chromosomal abnormalities was 6.4%.”

What the sources say

• ?Not checked — no full text of the sourcecites [87] Sagi-Dain, 2017, Risk for chromosomal aberrations in apparently isolated intrauterine growth restriction: A systematic review, Prenat Diagn source

In the paper

“The use of prophylactic lowdose aspirin was shown to provide a modest risk reduction in FGR and SGA in 2 meta-analyses.72,73”

What the sources say

• ?Not checked — no full text of the sourcecites [72] Roberge, 2017, The role of aspirin dose on the prevention of preeclampsia and fetal growth restriction: systematic review and meta-analysis, Am J Obstet Gynecol source
• ?Not checked — no full text of the sourcecites [73] Meher, 2017, Antiplatelet therapy before or after 16 weeks' gestation for preventing preeclampsia: an individual participant data meta-analysis, Am J Obstet Gynecol source

In the paper

“After correction for prematurity, survival without neurologic impairment was found to be significantly higher in the group delivered according to late ductus venosus changes (95%) compared with cSTV (85%).16”

What the sources say

• ?Not checked — no full text of the sourcecites [16] Lees, 2015, 2 year neurodevelopmental and intermediate perinatal outcomes in infants with very preterm fetal growth restriction (TRUFFLE): a randomised trial, Lancet source

In the paper

“Studies have found that 15%e20% of late-onset growthrestricted fetuses with normal umbilical blood flow have middle cerebral artery Doppler findings of cerebral vasodilation, and CPR has also been studied for its utility in predicting adverse outcomes and guiding the timing of delivery in late-onset cases.101,115,132e137”

What the sources say

• ?Not matched

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

  cites 101,115,132e137

In the paper

“therefore, the presence of a normal umbilical artery Doppler in late-onset FGR does not rule out placental disease.105,106”

What the sources say

• ?Not checked — no full text of the sourcecites [105] Morrow, 1989, Effect of placental embolization on the umbilical arterial velocity waveform in fetal sheep, Am J Obstet Gynecol source
• ?Not checked — no full text of the sourcecites [106] Thompson, 1989, Mathematical model for interpretation of Doppler velocity waveform indices, Med Biol Eng Comput source

In the paper

“results cannot be generalized to the visual interpretation of CTG.”

In the paper

“Even in pregnancies with AEDV/REDV of the umbilical artery, late Doppler abnormalities of the ductus venosus are noted in only about 41% of fetuses.117”

What the sources say

• ?Not checked — no full text of the sourcecites [117] Schwarze, 2005, Qualitative venous Doppler flow waveform analysis in preterm intrauterine growth-restricted fetuses with ARED flow in the umbilical artery--correlation with short-term outcome, Ultrasound Obstet Gynecol source

In the paper

“Pooled data from this meta-analysis also revealed a risk of stillbirth of 6.8% for AEDV and 19% for REDV in the umbilical artery or ductus venosus.100”

What the sources say

• ?Not checked — no full text of the sourcecites [100] Caradeux, 2018, Risk of fetal death in growth-restricted fetuses with umbilical and/or ductus venosus absent or reversed end-diastolic velocities before 34 weeks of gestation: a systematic review and meta-analysis, Am J Obstet Gynecol source

In the paper

“Reversed A-wave of the ductus venosus in FGR signifies more significant fetal cardiac compromise.119”

What the sources say

• ?Not checked — no full text of the sourcecites [119] Yagel, 2010, The fetal venous system, Part II: ultrasound evaluation of the fetus with congenital venous system malformation or developing circulatory compromise, Ultrasound Obstet Gynecol source

In the paper

“Experimental modeling suggests that a threshold of placental vascular obliteration is required before umbilical artery Doppler abnormalities are seen; therefore, the presence of a normal umbilical artery Doppler in late-onset FGR does not rule out placental disease.105,106”

What the sources say

• ?Not checked — no full text of the sourcecites [105] Morrow, 1989, Effect of placental embolization on the umbilical arterial velocity waveform in fetal sheep, Am J Obstet Gynecol source
• ?Not checked — no full text of the sourcecites [106] Thompson, 1989, Mathematical model for interpretation of Doppler velocity waveform indices, Med Biol Eng Comput source

In the paper

“This result is probably related to the lower frequency of placental pathologic findings in late-onset FGR when compared with early-onset FGR.102e104”

What the sources say

• ?Not matched

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

  cites 102e104

In the paper

“In a large study on FGR, the mean timeto-delivery interval for umbilical artery PI greater than the 95th percentile, AEDV, and REDV was 26, 13, and 4 days, respectively.62”

What the sources say

• ?Not checked — no full text of the sourcecites [62] Unterscheider, 2013, Predictable progressive Doppler deterioration in IUGR: does it really exist?, Am J Obstet Gynecol source

In the paper

“In general, this variation in umbilical artery Doppler end-diastolic flow along the umbilical cord is minimal and not significant enough to affect clinical decision-making.”

What the sources say

• ?Not matched

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

  cites [95] Trudinger, 1992, Doppler ultrasonography and fetal well-being

In the paper

“Data from this study showed that CPR evaluation had a sensitivity of 66% and specificity of 85% for the prediction of adverse outcomes.138”

What the sources say

• ?Not checked — no full text of the sourcecites [138] Flood, 2014, The role of brain sparing in the prediction of adverse outcomes in intrauterine growth restriction: results of the multicenter PORTO Study, Am J Obstet Gynecol source

In the paper

“In FGR, Doppler abnormalities of the ductus venosus primarily reflect increased central venous pressure, resulting from increased right ventricular end-diastolic pressure and decreased cardiac muscle compliance.110,118”

What the sources say

• ?Not checked — no full text of the sourcecites [110] Baschat, 2005, Arterial and venous Doppler in the diagnosis and management of early onset fetal growth restriction, Early Hum Dev source
• ?Not matched

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

  cites [118] Abuhamad, 2016

In the paper

“The progression from an abnormal umbilical artery Doppler with a decreased diastolic flow to AEDV/REDV can take several days to weeks, especially in the absence of maternal disease.”

In the paper

“Abnormal uterine artery Doppler, defined as a PI greater than the 95th percentile for gestational age or the presence of a diastolic notch, has been associated with adverse pregnancy outcomes, including preeclampsia, FGR, and perinatal mortality.137,141e147”

What the sources say

• ?Not matched

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

  cites 137,141e147

In the paper

“In a large European study, birthweights between the 10th and 25th percentiles were associated with a 2-fold increase in mortality when compared with the 50th to 75th percentile weight group.167”

What the sources say

• ?Not checked — no full text of the sourcecites [167] Zeitlin, 2010, Impact of fetal growth restriction on mortality and morbidity in a very preterm birth cohort, J Pediatr source

In the paper

“Severe early-onset FGR is characterized by failure of trophoblastic invasion of the myometrial spiral arteries, resulting in reduced uteroplacental perfusion.140”

What the sources say

• ?Not checked — no full text of the sourcecites [140] Sciscione, 2009, Uterine artery Doppler flow studies in obstetric practice, Am J Obstet Gynecol source

In the paper

“In a retrospective cohort study of pregnancies with FGR, no difference in composite neonatal outcome was seen between delivery at 39 weeks of gestation in fetuses with normal umbilical artery Doppler and delivery at 37 weeks of gestation in fetuses with elevated umbilical artery S/D ratio.168”

What the sources say

• ?Not checked — no full text of the sourcecites [168] Maggio, 2015, Perinatal outcomes with normal compared with elevated umbilical artery systolic-to-diastolic ratios in fetal growth restriction, Obstet Gynecol source

In the paper

“In the periviable period, the decision for delivery may be challenging because the rates of perinatal death, neurodevelopmental impairment, and other adverse outcomes are high in this gestational age window.157e159”

What the sources say

• ?Not matched

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

  cites 157e159

In the paper

“The PORTO study, which included more than 1100 pregnancies with FGR, noted that amniotic fluid volume abnormalities did not independently increase the risk for adverse outcomes in FGR. 30”

What the sources say

• ?Not checked — no full text of the sourcecites [30] Unterscheider, 2013, Optimizing the definition of intrauterine growth restriction: the multicenter prospective PORTO Study, Am J Obstet Gynecol source

In the paper

“Survival of very preterm neonates gradually decreases with decreasing weight percentiles.160e163”

What the sources say

• ?Not matched

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

  cites 160e163

In the paper

“In normal pregnancies, spiral artery remodeling results in a lowimpedance circulation, which is reflected in the uterine arteries by the presence of high velocity and continuous forward flow in diastole.140”

What the sources say

• ?Not checked — no full text of the sourcecites [140] Sciscione, 2009, Uterine artery Doppler flow studies in obstetric practice, Am J Obstet Gynecol source

In the paper

“There is currently a paucity of data on the role of amniotic fluid volume measurement in FGR management and delivery.30”

What the sources say

• ?Not checked — no full text of the sourcecites [30] Unterscheider, 2013, Optimizing the definition of intrauterine growth restriction: the multicenter prospective PORTO Study, Am J Obstet Gynecol source

In the paper

“Based on the available evidence, uterine artery Doppler does not add clinically valuable information for diagnosis or management.”

In the paper

“In the presence of REDV, neonatal morbidity and mortality rates are higher than complications of prematurity at 30e32 weeks of gestation.100”

What the sources say

• ?Not checked — no full text of the sourcecites [100] Caradeux, 2018, Risk of fetal death in growth-restricted fetuses with umbilical and/or ductus venosus absent or reversed end-diastolic velocities before 34 weeks of gestation: a systematic review and meta-analysis, Am J Obstet Gynecol source

In the paper

“As discussed previously, neonatal morbidity and mortality rates associated with AEDV are higher than rates of complications of prematurity at 33e34 weeks of gestation.100”

What the sources say

• ?Not checked — no full text of the sourcecites [100] Caradeux, 2018, Risk of fetal death in growth-restricted fetuses with umbilical and/or ductus venosus absent or reversed end-diastolic velocities before 34 weeks of gestation: a systematic review and meta-analysis, Am J Obstet Gynecol source

In the paper

“A large US cohort study reported that delivery at 37 weeks of gestation results in a decrease in the stillbirth rate in the presence of risk factors, such as FGR.169”

What the sources say

• ?Not checked — no full text of the sourcecites [169] Trudell, 2013, Risk of stillbirth after 37 weeks in pregnancies complicated by small-for-gestational-age fetuses, Am J Obstet Gynecol source

In the paper

“Neonatal mortality in SGA infants born between 24 and 29 weeks of gestation is increased 2-fold to 4-fold when compared with appropriately grown neonates.4,164e166”

What the sources say

• ?Not matched

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

  cites 4,164e166

In the paper

“The evidence supporting the timing of delivery in pregnancies with FGR and abnormal umbilical artery Doppler but without AEDV/REDV is limited.168”

What the sources say

• ?Not checked — no full text of the sourcecites [168] Maggio, 2015, Perinatal outcomes with normal compared with elevated umbilical artery systolic-to-diastolic ratios in fetal growth restriction, Obstet Gynecol source

In the paper

“Older studies reported rates of intrapartum fetal heart rate decelerations requiring cesarean delivery in 75%e95% of pregnancies with FGR and AEDV/REDV.172,173”

What the sources say

• ?Not checked — no full text of the sourcecites [172] Karsdorp, 1994, Clinical significance of absent or reversed end diastolic velocity waveforms in umbilical artery, Lancet source
• ?Not checked — no full text of the sourcecites [173] Forouzan, 1995, Absence of end-diastolic flow velocity in the umbilical artery: a review, Obstet Gynecol Surv source