The relationship between gestational weight gain, maternal upper-body subcutaneous fat changes and infant birth size: A pilot observational study amongst women with obesity

Analysis of risk factors and construction of a predictive model for macrosomia in deliveries with gestational diabetes

BACKGROUND

Gestational diabetes, a frequent pregnancy complication marked by elevated maternal blood glucose, can cause serious adverse effects for both mother and fetus, including increased amniotic fluid and risks of fetal asphyxia, hypoxia, and premature birth.

OBJECTIVE

To construct a predictive model to analyze the risk factors for macrosomia in deliveries with gestational diabetes.

METHODS

From January 2021 to February 2023, 362 pregnant women with gestational diabetes were selected for the study. They were followed up until delivery. Based on newborn birth weight, the participants were divided into the macrosomia group (birth weight ⩾ 4000 g) and the non-macrosomia group (birth weight < 4000 g). The data of the two groups of pregnant women were compared. ROC curves were plotted to analyze the predictive value of multiple factors for the delivery of macrosomic infants among pregnant women with gestational diabetes. A logistic regression model was constructed to identify the risk factors for delivering macrosomic infants and the model was tested.

RESULTS

A total of 362 pregnant women with gestational diabetes were included, of which 58 (16.02%) had babies with macrosomia. The macrosomia group exhibited higher metrics in several areas compared to those without: pre-pregnancy BMI, fasting glucose, 1 h and 2 h OGTT sugar levels, weight gain during pregnancy, and levels of triglycerides, LDL-C, and HDL-C, all with significant differences (P< 0.05). ROC analysis revealed predictive value for macrosomia with AUCs of 0.761 (pre-pregnancy BMI), 0.710 (fasting glucose), 0.671 (1 h OGTT), 0.634 (2 h OGTT), 0.850 (weight gain), 0.837 (triglycerides), 0.742 (LDL-C), and 0.776 (HDL-C), indicating statistical significance (P< 0.05). Logistic regression identified high pre-pregnancy BMI, fasting glucose, weight gain, triglycerides, and LDL-C levels as independent risk factors for macrosomia, with odds ratios of 2.448, 2.730, 1.884, 16.919, and 5.667, respectively, and all were statistically significant (P< 0.05). The model's AUC of 0.980 (P< 0.05) attests to its reliability and stability.

CONCLUSION

The delivery of macrosomic infants in gestational diabetes may be related to factors such as body mass index before pregnancy, blood-glucose levels, gain weight during pregnancy, and lipid levels. Clinical interventions targeting these factors should be implemented to reduce the incidence of macrosomia.

Anthropometric Changes During Pregnancy and Their Association with Adequacy of Gestational Weight Gain

Background

Gestational weight gain (GWG) is an expected component of a healthy pregnancy. Gaining weight within the recommended range helps support the mother's health by providing energy reserves and nutrients to meet the increased metabolic demands during pregnancy. Too much or too little GWG has been associated with adverse health outcomes for the mother and child.

Objective

The objective of the study was to examine how changes in anthropometric indicators during pregnancy, including fat gain, vary, compare changes among body mass index (BMI) (kg/m2) groups, and examine how the changes were associated with adequacy of GWG defined using the 2009 Institute of Medicine guidelines.

Methods

Data came from a cohort of 360 pregnant women with measured anthropometric indicators (weight, midupper arm circumference, and skin folds of the triceps, thigh, and upper iliac) at <12-, 16 to 22-, and 28 to 32-wks of gestation. Fat gain was calculated using a formula. Analysis of variance was used to test for differences in anthropometric changes by BMI and adequacy of GWG in the third trimester. Multiple logistic regression was used to examine associations between changes in anthropometric indicators and GWG recommendations.

Results

Women with normal weight had greater increases in all anthropometric indicators, which differed from women with obesity, who had negative changes and gained less weight. Women who gained inadequately (21%) had negative changes that were all less, compared with women who gained adequately (46%) (except in upper iliac) or excessively (34%). Women with BMI of >25 who gained adequately also had negative changes. Logistic regression results indicated that changes in midupper arm circumference, triceps, and thigh skin folds, and fat gain were all inversely associated with inadequate GWG, whereas all indicators were positively associated with excessive GWG.

Conclusions

Anthropometric changes during pregnancy differ by BMI and are associated with adequacy of GWG. Women who gained adequately had minimal fat gain, lending support for current GWG guidelines.

Maternal anthropometric measurements and correlation to maternal and fetal outcomes in late pregnancy

Background:

Body mass index does not distinguish between lean and fat body mass; therefore, its utility defining body composition is limited in pregnancy. Anthropometric measurements may better represent variation in body composition among women who are overweight or obese. We sought to examine body fat composition using maternal anthropometric measurements in late pregnancy and correlate with mode of delivery.

Methods:

A prospective study of pregnant patients who were overweight (body mass index: 25–29.9 kg/m²) or obese (body mass index ⩾ 30 kg/m²) with singleton pregnancies who underwent anthropometric measurements between 27 weeks, 0 days to 34 weeks, 6 days gestation. Maternal skinfold thicknesses from eight sites were used to estimate body fat mass. Correlation of skinfold thickness, anthroprometric measurements, and estimated body fat percentage on mode of delivery were analyzed with p < .05 as significant.

Results:

A total of 41 women with overweight (34.1%) or obese (65.9%) body habitus were included. Mean age was 29.9 years, and the majority (43.9%) were Black and 31.7% identified Hispanic/Latinx. The average gestational age at recruitment was 30 weeks, 2 days and 38 weeks, 6 days at delivery. A greater weight at recruitment (94.2 vs 81.8 kg, p = .023), waist circumference (47.1 vs 43.5 inches, p = .010), Huston–Presley body fat percentage (36.4% vs 31.8%, p = .030), triceps skinfold thickness (20.1 vs 15.7 mm, p = .030), biceps skinfold thickness (18.6 vs 15.0 mm, p = .042), and skinfold thickness, as well as sum of skinfold sites (83.3 vs 68.8 mm, p = .049) were associated with cesarean delivery compared to vaginal delivery on univariate analysis.

Conclusion:

Third-trimester anthropometric measurements may help predict increased risk for c-section in women with obesity. Further research may elucidate utility in nutritional counseling and delivery planning.