Background: Studies of antiretroviral therapy (ART) use during pregnancy in HIVinfected women have suggested that ART exposure may be associated with adverse birth outcomes. However, there are few data from sub-Saharan Africa where HIV is most common, and few studies involving the World Health Organization’s (WHO’s) recommended first-line regimens. Methods: We enrolled consecutive HIV-infected pregnant women and a comparator cohort of uninfected women at a primary-level antenatal care facility in Cape Town, South Africa. Gestational assessment combined clinical history, examination and ultrasonography; outcomes included preterm (PTD), low birthweight (LBW) and small for gestational age (SGA) deliveries. In analysis we compared birth outcomes between HIVinfected and -uninfected women, and HIV-infected women who initiated ART before vs during pregnancy. Results: In 1554 women (mean age 29 years) with live singleton births at time of analysis, 82% were HIV-infected, 92% of whom received a first-line regimen of tenofovir, emtricitabine and efavirenz. Overall, higher levels of PTD [22% vs 13%; odds ratio (OR) 1.94, 95% confidence interval (CI): 1.34, 2.82] and LBW (14% vs 9%; OR 1.62, 95% CI: 1.05, 2.29) were observed in HIV-infected vs uninfected women, although SGA deliveries were similar (9% vs 11%; OR 1.06, 95% CI: 0.71, 1.61). Adjusting for demographic characteristics and HIV disease measures, HIV-infected (vs HIV-uninfected) women had persistently increased odds of PTD [adjusted odds ratio (AOR) 2.03; CI 1.33, 3.10]; associations with LBW were attenuated (AOR 1.47; CI 0.90, 2.40). Among all HIV-infected women, there appeared to be no association between the timing of ART initiation (before or during pregnancy) and adverse birth outcomes. Conclusions: These findings suggest that current WHO-recommended ART regimens appear relatively safe in pregnancy, although more data are required to understand the aetiology of preterm delivery in HIV-infected women using ART.
This prospective cohort study was conducted among consecutive HIV-infected and HIV-uninfected women seeking antenatal care (ANC) at a large, community-based public sector primary care facility in Cape Town, South Africa, enrolled between April 2013 and August 2015. The facility serves a catchment population of approximately 350 000 where ANC uptake is high (95%); in 2014, the antenatal HIV seroprevalence was estimated at 30%.26 All women in this setting have gestational age estimated based on last menstrual period (LMP) and symphysis-fundal height (SFH) at the first ANC visit, as part of routine clinical care at their first ANC visit. All women without a previous HIV diagnosis underwent HIV testing, with ART eligibility based on CD4 cell count <350 cells/µl or WHO stage III/IV disease (from April to June 2013) or universal ART eligibility, regardless of CD4 cell count or disease stage (July 2013 onwards). HIV-infected women conceiving while on ART continued their current regimen throughout pregnancy; regimens included PIs (used in this setting predominantly after failure of first-line therapy) or NNRTIs such as EFV or nevirapine (NVP, used in previous first-line regimens). For women initiating ART in pregnancy, a fixed-dose combination of TDF + FTC + EFV was used throughout. Following ART initiation, clinical follow-up was through an integrated primary care service providing antenatal and HIV care. This analysis draws on data from a larger multicomponent study of antiretroviral services for HIV-infected women during pregnancy and postpartum [https://clinicaltrials.gov/ct2/show/{"type":"clinical-trial","attrs":{"text":"NCT01933477","term_id":"NCT01933477"}}NCT01933477].27 HIV-uninfected women were enrolled consecutively into a separate comparator cohort with identical study procedures. The parent study was reviewed and approved by the University of Cape Town Faculty of Health Sciences Human Research Ethics Committee and Columbia University Medical Center Institutional Review Board. Written informed consent was obtained from all participants at their first ANC visit, and this consent included access to their clinical records for this birth outcomes analysis. Consecutive women (aged ≥ 18 years) attending their first antenatal care visit, who were identified as HIV-infected through routine rapid antibody tests, were eligible for enrolment into the HIV-infected cohort. Women not eligible for ART at their first ANC visit (receiving zidovudine prophylaxis) were excluded from this analysis. For the comparator HIV-uninfected cohort, women were eligible for enrolment based on the same criteria and a negative test on the same routine rapid antibody test. All women (HIV-infected and HIV-uninfected) completed questionnaires including demographics and obstetric and medical history. HIV-infected women provided 5 ml of blood for viral load (VL) testing using Abbot Realtime HIV-1 assay (Abbot Laboratories, Waltham, MA). At their first visit, an obstetric ultrasound (US) was performed on all women by an experienced research sonographer using a standardized assessment protocol and blinded to other clinical details. Follow-up study interviews, separate from routine clinical care, were scheduled around the second ANC visit, late third trimester and within 7 days postpartum. Obstetric outcomes, including date and mode of delivery and birthweight, were abstracted from obstetric records at delivery facilities. In analysis, gestation was based on completed weeks using the best available measure (US or combination of LMP/SFH at later gestations). HIV/ART status (the exposure of interest) was categorized as: (i) HIV-uninfected; (ii) ART initiated before pregnancy; and (iii) ART initiated during pregnancy in the (a) first trimester (<14 weeks), (b) first half of the second trimester (14–20 weeks), (c) second half of the second trimester (21–27 weeks) or (d) third trimester (≥28 weeks). Regimens were categorized as either PI or NNRTI; NNRTI regimens were either EFV-based [TDF + 3TC (lamivudine) + EFV], NVP-based (TDF + 3TC + NVP) or involving other NNRTIs. All deliveries before September 2015 were included in analysis. PTD was defined as delivery at <37 weeks’ gestation, categorized as late preterm (34–37 weeks), moderately preterm (32–34 weeks) or very preterm (<32weeks). LBW was defined as birthweight < 2500 g and very low birthweight (VLBW) as <1500 g. Using the INTERGROWTH-21st Project Standards, infants with birthweights 90th percentile were classified large for gestational age (LGA).28,29 Composite pregnancy loss was defined as any loss before delivery, and included: ectopic pregnancies as determined by the research sonographer; miscarriages defined as pregnancy loss <28 weeks;30 and stillbirths defined as fetal death occurring before/during labour and delivery (based on a 1-min APGAR score of 0). Statistical analyses (STATA 14.0, Stata Corporation, College Station, TX, USA) focused on three exposure comparisons: HIV-infected vs HIV-uninfected women (Comparison A); among HIV-infected women, those initiating ART before pregnancy vs those initiating during pregnancy (Comparison B); and among women initiating ART during pregnancy, comparisons across gestational ages at ART initiation (Comparison C). Pregnancy outcome analyses were restricted to live singleton births. In bivariable analyses, proportions were compared using chi-square and rank sum tests. Birth outcomes (PTD, LBW and SGA) were compared using unadjusted and adjusted logistic regression; results are presented as odds ratios (OR) with 95% confidence intervals (CI). Confounders identified a priori included age, maternal height, parity and previous PTD; and among HIV-infected women, pre-ART CD4 count and pre-ART viral load (VL). Subgroup analyses involved restrictions by EFV or PI use, and by gestation at first ANC visit. Model fit was assessed using likelihood ratio tests and Akaike’s Information Criterion; throughout, statistical tests were two-sided (alpha = 0.05).