UCSF

Background

We evaluated associations between antepartum weight change and adverse pregnancy outcomes and between antiretroviral therapy (ART) regimens and week 50 postpartum body mass index in IMPAACT 2010.

Methods

Women with human immunodeficiency virus (HIV)-1 in 9 countries were randomized 1:1:1 at 14-28 weeks' gestational age (GA) to start dolutegravir (DTG) + emtricitabine (FTC)/tenofovir alafenamide fumarate (TAF) versus DTG + FTC/tenofovir disoproxil fumarate (TDF) versus efavirenz (EFV)/FTC/TDF. Insufficient antepartum weight gain was defined using Institute of Medicine guidelines. Cox-proportional hazards regression models were used to evaluate the association between antepartum weight change and adverse pregnancy outcomes: stillbirth (≥20 weeks' GA), preterm delivery (<37 weeks' GA), small size for GA (<10th percentile), and a composite of these endpoints.

Results

A total of 643 participants were randomized: 217 to the DTG + FTC/TAF, 215 to the DTG + FTC/TDF, and 211 to the EFV/FTC/TDF arm. Baseline medians were as follows: GA, 21.9 weeks; HIV RNA, 903 copies/mL; and CD4 cell count, 466/μL. Insufficient weight gain was least frequent with DTG + FTC/TAF (15.0%) versus DTG + FTC/TDF (23.6%) and EFV/FTC/TDF (30.4%). Women in the DTG + FTC/TAF arm had the lowest rate of composite adverse pregnancy outcome. Low antepartum weight gain was associated with higher hazard of composite adverse pregnancy outcome (hazard ratio, 1.44 [95% confidence interval, 1.04-2.00]) and small size for GA (1.48 [.99-2.22]). More women in the DTG + FTC/TAF arm had a body mass index ≥25 (calculated as weight in kilograms divided by height in meters squared) at 50 weeks postpartum (54.7%) versus the DTG + FTC/TDF (45.2%) and EFV/FTC/TDF (34.2%) arms.

Conclusions

Antepartum weight gain on DTG regimens was protective against adverse pregnancy outcomes typically associated with insufficient weight gain, supportive of guidelines recommending DTG-based ART for women starting ART during pregnancy. Interventions to mitigate postpartum weight gain are needed.