Background: Before introduction of tenofovir/emtricitabine/efavirenz (TDF/FTC/EFV), 3-drug antiretroviral therapy (ART) was associated with increased adverse birth outcomes when used for prevention of mother-to-child HIV transmission (PMTCT) in Botswana.

Methods: We extracted obstetric records from all women at the 2 largest maternities in Botswana from 2009-2011 when Botswana National Guidelines recommended zidovudine (ZDV) from 28 weeks gestational age (GA) for CD4 ≥350 and ART for CD4 <350, and again in 2013-2014 after implementation of TDF/FTC/EFV for prevention of mother-to-child HIV transmission regardless of CD4 or GA. We compared the use of TDF/FTC/EFV in pregnancy with other 3-drug ART regimens, and with initiation of ZDV, among women with similar CD4 cell counts. Outcomes included small for gestational age (SGA), preterm delivery (PTD) (<37 weeks GA), and stillbirths (SB).

Results: Among 9445 HIV-infected women delivering during the study period, 170 were on TDF/FTC/EFV at conception and 1468 initiated TDF/FTC/EFV during pregnancy. Adverse birth outcomes were high overall (3% SB, 21% PTD, and 18% SGA) and among women receiving TDF/FTC/EFV (3% SB, 22% PTD, and 12% SGA). There was no difference in PTD or SB among women initiating TDF/FTC/EFV compared with ZDV or other 3-drug ART, but initiating TDF/FTC/EFV was associated with fewer SGA infants than other 3-drug ART (adjusted odds ratio: 0.4, 95% confidence interval: 0.2 to 0.7).

Conclusions: Adverse birth outcomes remain high among HIV-infected women. TDF/FTC/EFV was at least as safe as other ART and associated with fewer SGA infants when initiated during pregnancy. Larger studies are needed to evaluate birth outcomes and congenital abnormalities among women on TDF/FTC/EFV at conception.