The P4 Study: 6 months postpartum body composition in normotensive vs hypertensive pregnancies

Increased postpartum weight retention, a risk factor for long-term obesity and cardiometabolic diseases, is greater following hypertensive disorders of pregnancy (HDP), possibly mediated by body composition (BC) changes. However, normative postpartum BC data are lacking. This study aimed to: (1) construct a reference range for BC in normotensive women 6 months postpartum for Caucasian and Asian populations, (2) compare BC 6 months postpartum between women who had a normotensive pregnancy (NP), gestational hypertension (GH) and preeclampsia (PE) in pregnancy, and (3) explore predictors of postpartum BC. Cross-sectional analysis 6 months postpartum from the Postpartum, Physiology, Psychology and Paediatrics (P4) prospective cohort study of women after NP, GH and PE. The main BC measures were body fat percentage (BF%), fat mass, adipose tissue mass, lean tissue mass, and relative lean tissue mass determined using bio-impedance analysis at 6 months postpartum. 388 women were included: 280 NP, 21 GH, 87 PE. 10th-90th percentile range for BF% was 24-47 % amongst all NP women, 24-47 % for Caucasian, and 21-44 % for Asian (p = 0.016). Average postpartum BF% was highest after GH (44 ± 7 %), followed by PE (39 ± 9 %) and NP (36 ± 9 %) [p < 0.001]. Significant predictors of higher postpartum BF% were HDP, Caucasian ethnicity, gestational diabetes mellitus, higher antenatal Edinburgh Depression Scale (EDS) score, and breastfeeding cessation by 6 months. A postpartum BC reference range for NP, which differs between Caucasian and Asian women, was established. Experiencing HDP was independently associated with increased postpartum BF%, which may contribute to longer-term obesity and cardiometabolic risks.