Objective: To examine associations between maternal body mass index (BMI), gestational weight gain (GWG) and fetal growth and neonatal adiposity in urban South Africans.
Methods: Maternal BMI was assessed at recruitment and GWG (kg/week) was calculated. Longitudinal fetal growth was measured via ultrasound and modelled using Superimposition by Translation and Rotation (SITAR). Neonatal adiposity was assessed using air displacement plethysmography or dual-energy X-ray absorptiometry. Multiple linear regression models were used to examine associations between maternal BMI, GWG and SITAR fetal growth parameters and neonatal fat mass index (FMI; kg/m3 ) in 304 mother-neonate pairs.
Results: In pooled analyses, longitudinally modelled abdominal circumference size (β = 0.64 kg/m3 , P < .001) and velocity (β = 8.39 kg/m3 , P < .001) and biparietal diameter velocity (β = 4.55 kg/m3 , P = .020) were positively associated with neonatal FMI. GWG was positively associated with neonatal FMI in preliminary models (β = 1.07 kg/m3 per 1 kg/week; P = .040), with pooled models indicating mediation via fetal growth.
Conclusion: In utero abdominal growth is predictive of neonatal adiposity. Additionally, greater fetal growth - particularly of the abdominal circumference - mediates the effect of GWG on neonatal adiposity. In settings such as South Africa, strategies to ensure healthy pregnancy weight gain can contribute to prevention of intergenerational obesity risk.
© 2020 World Obesity Federation.