Race-based customization of fetal growth standards - What is the impact on disparities?

Abstract Background The impact of using the Intergrowth (IG) dating formulae in comparison to the commonly used Robinson dating on the evaluation of biometrics and estimated fetal weight (EFW) has not been evaluated. Methods Nationwide cross-sectional study of routine fetal ultrasound biometry in low-risk pregnant women whose gestational age (GA) had been previously assessed by a first trimester CRL measurement. We compared the CRL-based GA according to the Robinson formula and the IG formula. We evaluated the fetal biometric measurements as well as the EFW taken later in pregnancy depending on the dating formula used. Mean and standard deviation of the Z scores as well as the number and percentage of cases classified as <3rd, < 10th, >90th and > 97th percentile were compared. Results Three thousand five hundred twenty-two low-risk women with scans carried out after 18 weeks were included. There were differences of zero, one and 2 days in 642 (18.2%), 2700 (76.7%) and 180 (5%) when GA was estimated based on the Robinson or the IG formula, respectively. The biometry Z scores assessed later in pregnancy were all statistically significantly lower when the Intergrowth-based dating formula was used (p < 10− 4). Likewise, the number and percentage of foetuses classified as <3rd, < 10th, >90th and > 97th percentile demonstrated significant differences. As an example, the proportion of SGA foetuses varied from 3.46 to 4.57% (p = 0.02) and that of LGA foetuses from 17.86 to 13.4% (p < 10− 4). Conclusion The dating formula used has a quite significant impact on the subsequent evaluation of biometry and EFW. We suggest that the combined and homogeneous use of a recent dating standard, together with prescriptive growth standards established on the same low-risk pregnancies, allows an optimal assessment of fetal growth.

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One size fits all? A call to establish Taiwanese fetal growth standards

Taiwanese Journal of Obstetrics and Gynecology ◽

10.1016/j.tjog.2020.03.027 ◽

2020 ◽

Vol 59 (3) ◽

pp. 468

Author(s):

Ksenia Olisova ◽

Chan-Yu Sung ◽

Yi-Ying Li ◽

Ching-Chi Hsia ◽

Tung-Yao Chang

Keyword(s):

Fetal Growth ◽

Growth Standards

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Genomic imbalances in the placenta are associated with poor fetal growth

Molecular Medicine ◽

10.1186/s10020-020-00253-4 ◽

2021 ◽

Vol 27 (1) ◽

Author(s):

Giulia F. Del Gobbo ◽

Yue Yin ◽

Sanaa Choufani ◽

Emma A. Butcher ◽

John Wei ◽

...

Keyword(s):

Fetal Growth ◽

Sex Chromosome ◽

Copy Number Variants ◽

Placental Insufficiency ◽

Potential Contribution ◽

Genomic Imbalances ◽

Significant Difference ◽

Underlying Causes ◽

Risk Of Disease ◽

The Impact

Abstract Background Fetal growth restriction (FGR) is associated with increased risks for complications before, during, and after birth, in addition to risk of disease through to adulthood. Although placental insufficiency, failure to supply the fetus with adequate nutrients, underlies most cases of FGR, its causes are diverse and not fully understood. One of the few diagnosable causes of placental insufficiency in ongoing pregnancies is the presence of large chromosomal imbalances such as trisomy confined to the placenta; however, the impact of smaller copy number variants (CNVs) has not yet been adequately addressed. In this study, we confirm the importance of placental aneuploidy, and assess the potential contribution of CNVs to fetal growth. Methods We used molecular-cytogenetic approaches to identify aneuploidy in placentas from 101 infants born small-for-gestational age (SGA), typically used as a surrogate for FGR, and from 173 non-SGA controls from uncomplicated pregnancies. We confirmed aneuploidies and assessed mosaicism by microsatellite genotyping. We then profiled CNVs using high-resolution microarrays in a subset of 53 SGA and 61 control euploid placentas, and compared the load, impact, gene enrichment and clinical relevance of CNVs between groups. Candidate CNVs were confirmed using quantitative PCR. Results Aneuploidy was over tenfold more frequent in SGA-associated placentas compared to controls (11.9% vs. 1.1%; p = 0.0002, OR = 11.4, 95% CI 2.5–107.4), was confined to the placenta, and typically involved autosomes, whereas only sex chromosome abnormalities were observed in controls. We found no significant difference in CNV load or number of placental-expressed or imprinted genes in CNVs between SGA and controls, however, a rare and likely clinically-relevant germline CNV was identified in 5.7% of SGA cases. These CNVs involved candidate genes INHBB, HSD11B2, CTCF, and CSMD3. Conclusions We conclude that placental genomic imbalances at the cytogenetic and submicroscopic level may underlie up to ~ 18% of SGA cases in our population. This work contributes to the understanding of the underlying causes of placental insufficiency and FGR, which is important for counselling and prediction of long term outcomes for affected cases.

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Fetal growth standards for Chinese twin pregnancies

BMC Pregnancy and Childbirth ◽

10.1186/s12884-021-03926-y ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Jianping Chen ◽

Jun Zhang ◽

Yang Liu ◽

Xing Wei ◽

Yingjun Yang ◽

...

Keyword(s):

Fetal Growth ◽

Mixed Model ◽

Linear Mixed Model ◽

Perinatal Outcomes ◽

Growth Charts ◽

Growth Standards ◽

Growth Standard ◽

Adverse Perinatal Outcomes ◽

Chinese Twins ◽

Twin Pregnancies

Abstract Background The common use of singleton fetal growth standard to access twin growth might lead to over-monitoring and treatment. We aimed to develop fetal growth standards for Chinese twins based on ultrasound measurements, and compare it with Zhang’s and other twin fetal growth charts. Methods A cohort of uncomplicated twin pregnancies were prospectively followed in 2014–2017. Smoothed estimates of fetal growth percentiles for both monochorionic (MC) and dichorionic (DC) twins were obtained using a linear mixed model. We also created growth charts for twins using a model-based approach proposed by Zhang et al. Our twin standards were compared with Hadlock’s (singleton) in predicting adverse perinatal outcomes. Results A total of 398 twin pregnancies were included, with 214 MC and 582 DC live-born twins. The MC twins were slightly lighter than the DC twins, with small differences throughout the gestation. Our ultrasound-based fetal weight standards were comparable to that using Zhang’s method. Compared with previous references/standards from the US, Brazil, Italy and UK, our twins had very similar 50th percentiles, but narrower ranges between the 5th and 95th or 10th and 90th percentiles. Compared with the Hadlock’s standard, the risks of neonatal death and adverse perinatal outcomes for small for gestational age (SGA) versus non-SGA were substantially elevated using our standards. Conclusions A normal fetal growth standard for Chinese twins was created. The differences between MC and DC twins were clinically insignificant. The 50th weight percentiles of the Chinese twins were identical to those in other races/ethnicities but the ranges were markedly narrower. Our standard performed much better than the Hadlock’s in predicting low birth weight infants associated with adverse perinatal outcomes in twin pregnancies. The present study also indicated that Zhang’s method is applicable to Chinese twins, and other areas may use Zhang’s method to generate their own curves for twins if deemed necessary.

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Understanding the impact of metformin on maternal health and fetal growth in pregnancies complicated by maternal diabetes

http://isrctn.com/ ◽

10.1186/isrctn13866189 ◽

2021 ◽

Author(s):

Jenny Myers

Keyword(s):

Maternal Health ◽

Fetal Growth ◽

Maternal Diabetes ◽

The Impact

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Maternal Oxidative Stress, Placental Morphometry, and Fetal Growth in Diabetic Rats Exposed to Cigarette Smoke

Reproductive Sciences ◽

10.1177/1933719118815589 ◽

2018 ◽

Vol 26 (9) ◽

pp. 1287-1293 ◽

Cited By ~ 4

Author(s):

Yuri K. Sinzato ◽

Estela M. Bevilacqua ◽

Gustavo T. Volpato ◽

Rogelio E. Hernandez-Pando ◽

Marilza V. C. Rudge ◽

...

Keyword(s):

Oxidative Stress ◽

Cigarette Smoke ◽

Fetal Growth ◽

Fetal Development ◽

Oxidative Stress Biomarkers ◽

Junctional Zone ◽

Pregnant Rats ◽

Stress Biomarkers ◽

Vascular Walls ◽

The Impact

The diabetic syndrome affects pregnancy, contributing to placental functional and structural disruptions and impaired fetal development, with many reports indicating tobacco-associated morbidity and perinatal mortality. In our study, an experimental rat model of diabetes and cigarette smoke exposure in pregnant rats was used to determine the impact of the combination of diabetes and exposure to cigarette smoke during pregnancy on maternal oxidative stress biomarkers and placental and fetal development. Diabetes was induced by streptozotocin, and dams were exposed to cigarette smoke by mainstream smoke generated by a mechanical smoking device and delivered into a chamber. Four groups of dams were studied: nondiabetic (C, control) and diabetic (D) exposed to filtered air and nondiabetic (CS) and diabetic (DS) exposed to cigarette smoke prior to and during pregnancy. Maternal oxidative stress biomarkers, placental morphology, and fetal growth were determined close to term. The combination of diabetes and cigarette smoke resulted in elevated maternal blood glucose levels and increased number of small fetuses. Placentas from the DS group showed increased junctional zone and decreased labyrinthine area. The morphological alterations were characterized by extensive vascular congestion, thickness, and hyalinization of the vascular walls, numerous decidual cells with abundant glycogen, and macrophages with cytoplasmic inclusions of hemosiderin. Additionally, they showed increased glycogen accumulation and junctional zone structural derangement with ectopic giant cells. No alterations were observed in maternal oxidative stress status. Thus, our result suggests that diabetes makes pregnant rats more susceptible to the adverse effects of exposure to cigarette smoke on placental morphometry and fetal growth.

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