BACKGROUND: Antiretroviral therapy (ART) during pregnancy reduces the risk of perinatal transmission of HIV-1 but may increase the risk of pregnancy complications. Pregnancy may enhance toxicity of ART. We evaluated rates of maternal toxicity, adverse pregnancy outcomes, and maternal peripartum morbidity according to the type and duration of ART taken during pregnancy.

METHODS: PACTG 316 evaluated if the addition of intrapartum/neonatal nevirapine to established ART during pregnancy reduced perinatal transmission of HIV-1. Detailed data were collected on maternal ART use throughout pregnancy. For this analysis, women were categorized into 1 of 6 groups based on type of therapy during pregnancy (monotherapy [monoRx], combination without protease inhibitor [PI], combination with PI) and start date (early = before pregnancy or during first trimester, late = begun second or third trimester). Outcomes were determined from signs/symptoms, diagnoses, laboratory results forms prospectively completed on study at enrollment, delivery and 6 wks postpartum.

RESULTS: A total 1,409 women were included in the analysis: 290 monoRx early, 34 monoRx late, 175 combo no PI early, 327 combo no PI late, 263 combo PI early, and 320 combo PI late. The most common symptoms anytime during pregnancy (moderate grade or higher) were vaginal bleeding 5.5%, nausea/vomiting 2.7%, and headache 2.2%. The most frequent lab abnormalities were anemia ( 2.5 x ULN) 1.1%. Mean gestational age at delivery was 38.1 wks and mean birth weight was 3078 g. Stillbirth occurred in 0.4%. Bacterial pneumonia occurred in 3% of women and AIDS-associated pneumonia in 2% during pregnancy or the postpartum period. Peripartum complication rates were low and depended on delivery mode. Event rates did not differ by antiretroviral group or study treatment assignment.

CONCLUSIONS: In this population of HIV-infected women receiving prenatal care and ART, adverse events were uncommon and did not differ by type and duration of ART. Pneumonia occurred relatively frequently during pregnancy.