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

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.

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.

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.

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.