Implications of maternal obesity on fetal growth and the role of ultrasound

A retrospective cohort study on the influencing factors for macrosomia in singleton pregnancies

To explore the influencing factors of singletons with macrosomia, and to develop interventions for the prevention of macrosomia. A retrospective cohort study was conducted on 26,379 pregnant women who established the Maternal and Child Health Record and gave birth from January 1, 2019 to December 31, 2019 in a community health service center in Haidian district, Beijing. The study analyzed factors such as maternal age, ethnicity, education level, prepregnancy body mass index (BMI), parity, folic acid supplementation, gestational diabetes mellitus, gestational hyper, hypothyroidism in pregnancy (including subhypothyroidism), hyperthyroidism in pregnancy, and infant gender. Univariate analysis was performed using the χ2 test, and multivariate analysis was performed using non-conditional multivariate logistic regression analysis. Out of 26,379 live births, 5.8% (1522/26,379) were macrosomia and 94.2% (24,857/26,379) were non-macrosomia. Univariate analysis revealed that maternal age, prepregnancy BMI, education level, parity, hypothyroidism during pregnancy, and infant gender were identified as influencing factors for macrosomia (P < .05). Multivariate analysis showed that maternal age ≥ 35 years, education level of high school or below, pre-pregnancy BMI, hypothyroidism, male infant, and parity were all influencing factors for macrosomia (P < .05). Prepregnancy overweight or obesity, male infants, multiparity, and low education level are risk factors for macrosomia. Multiple factors can contribute to macrosomia, and therefore, maternal health care should be strengthened, and early interventions should be taken for the above-mentioned factors in the local area.

A routine third trimester growth ultrasound in the obese pregnant woman does not reliably identify fetal growth abnormalities: A retrospective cohort study

BACKGROUND

In response to the challenges of assessing fetal growth in obese women, guidelines recommend routine third trimester ultrasound scans.

AIM

The aim of this study was to assess the diagnostic performance of this routine scan in obese women (body mass index (BMI) ≥ 35 kg/m² ).

METHODS

A retrospective cohort study of 1008 pregnancies with maternal BMI ≥ 35 kg/m² born after 37 weeks gestation at a Victorian hospital from 2015 to 2017. Multiple pregnancies and those affected by diabetes were excluded. Growth ultrasounds were performed between 34 + 0 and 36 + 6 weeks gestation. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for the detection of large for gestational age (LGA > 90%) and small for gestational age (SGA < 10%) were calculated using ultrasound estimated fetal weight (EFW) or abdominal circumference (AC) and compared with gestational age and gender-based birthweight percentiles.

RESULTS

Using EFW, sensitivity for detecting SGA at birth was 8.1% (six of 74) with a PPV of 100%. Sensitivity for detecting LGA at birth was 61.0% (119 of 195), PPV 54.8%. Sensitivity, specificity, PPV and NPV percentages were all lower using AC. Only 40% of actual birthweight percentiles (405/1008) were within ±10 percentiles of their growth ultrasound EFW percentile.

CONCLUSION

The performance of a routine third trimester ultrasound in women with BMI ≥ 35 kg/m² suggests limited utility in helping identify aberrant fetal growth. This has important implications for the management of obese pregnant women.

The Effects of Selenium Supplementation on Gene Expression Related to Insulin and Lipid Metabolism, and Pregnancy Outcomes in Patients with Gestational Diabetes Mellitus: a Randomized, Double-Blind, Placebo-Controlled Trial

This study was performed to evaluate the effects of selenium supplementation on gene expression related to insulin and lipid metabolism, and pregnancy outcomes in patients with gestational diabetes mellitus (GDM). The current randomized, double-blind, placebo-controlled clinical trial was conducted in 36 patients with GDM. Participants were randomly divided into two groups to intake either 200 μg/day selenium supplements as selenium yeast or placebo (n = 18 each group) for 6 weeks. Selenium supplementation upregulated peroxisome proliferator-activated receptor gamma (P = 0.03) and glucose transporter 1 (GLUT-1) (P = 0.01) in lymphocytes of subjects with GDM compared with the placebo. Selenium supplementation did not affect gene expression of low-density lipoprotein receptor (LDLR) and lipoprotein(a) [Lp(a)]. Supplementation with selenium had a significant decrease in incidence of newborns' hyperbilirubinemia (5.6% vs. 33.3%, P = 0.03) and newborns' hospitalization (5.6% vs. 33.3%, P = 0.03) compared with the placebo. Overall, we found that selenium supplementation for 6 weeks among patients with GDM significantly increased PPAR-γ and GLUT-1 expression, but did not affect gene expression of LDLR and LP(a). It also reduced incidence of newborns' hyperbilirubinemia and newborns' hospitalization. Clinical trial registration number: http://www.irct.ir: IRCT20170513033941N35.

Biomarkers for Macrosomia Prediction in Pregnancies Affected by Diabetes

Large birthweight, or macrosomia, is one of the commonest complications for pregnancies affected by diabetes. As macrosomia is associated with an increased risk of a number of adverse outcomes for both the mother and offspring, accurate antenatal prediction of fetal macrosomia could be beneficial in guiding appropriate models of care and interventions that may avoid or reduce these associated risks. However, current prediction strategies which include physical examination and ultrasound assessment, are imprecise. Biomarkers are proving useful in various specialties and may offer a new avenue for improved prediction of macrosomia. Prime biomarker candidates in pregnancies with diabetes include maternal glycaemic markers (glucose, 1,5-anhydroglucitol, glycosylated hemoglobin) and hormones proposed implicated in placental nutrient transfer (adiponectin and insulin-like growth factor-1). There is some support for an association of these biomarkers with birthweight and/or macrosomia, although current evidence in this emerging field is still limited. Thus, although biomarkers hold promise, further investigation is needed to elucidate the potential clinical utility of biomarkers for macrosomia prediction for pregnancies affected by diabetes.

Second trimester ultrasound detection of fetal anomalies in the obese obstetrical population: a systematic review protocol

REVIEW QUESTION/OBJECTIVE

The objective of this review is to identify, appraise and synthesize the best available evidence on the impact of maternal obesity on mid second trimester ultrasound detection of fetal anomalies in pregnancy.