To assess the relationship between infant feeding, triple-antiretroviral prophylaxis and weight from 2 weeks (baseline) to 6 months postpartum among HIV-infected mothers in a mother-to-child transmission (MTCT) of HIV-prevention trial in five sub-Saharan African sites.

HIV-infected pregnant women with CD4 cell counts of 200-500 cells/μl were counselled to choose breastfeeding to 6 months or replacement feeding from delivery. They were randomized to receive perinatal zidovudine and single-dose nevirapine or triple-antiretroviral MTCT prophylaxis until breastfeeding cessation. Mixed-effect linear models were used to compare maternal weight trajectories over time by infant feeding mode. Antiretroviral prophylaxis and BMI at baseline were examined as potential effect modifiers.

Among 797 mothers, 620 (78%) initiated breastfeeding. Wasting (BMI <18.5) was rare at baseline (2%), whereas overweight/obesity (BMI ≥ 25) was common (40%). In the model including all women, breastfeeding was not associated with weight loss up to 6 months, irrespective of baseline BMI and antiretroviral prophylaxis. Triple-antiretroviral prophylaxis was associated with weight gain among replacement-feeding mothers with baseline BMI at least 25 (+0.54 kg/month; P < 0.0001). In the model including breastfeeding mothers only, triple-antiretroviral prophylaxis was associated with weight gain among mothers with baseline BMI at least 25 who ceased breastfeeding before 3 months postpartum (+0.33 kg/month; P = 0.03).

The results suggest that breastfeeding up to 6 months postpartum is not detrimental for postpartum weight among well nourished HIV-infected mothers at intermediate-disease stage. In the absence of breastfeeding or after weaning, triple-antiretroviral prophylaxis is associated with weight gain among women with high BMI, even after cessation of prophylaxis.