For women enrolled in both the MoCHiV and the SHCS, precise information on ART prior to and during pregnancy as well as on clinical characteristics (e.g. CD4 cell count, viral load and the presence of opportunistic infections) and possible (behavioural) risk factors for premature birth (such as smoking and illicit drug use) before and during pregnancy has become available. All data were reported prospectively on structured worksheets and entered into the national database at the coordinating centre. Informed consent was obtained from each woman participating in the SHCS and for each child’s parents or legal guardians before enrolment into the MoCHiV, and local institutional ethics committee CDK inhibitor approval

was obtained for both the SHCS and the MoCHiV. Analyses were restricted to HIV-1-positive women with a history of at least one pregnancy that was completed to live birth, excluding multiple (twin) pregnancies, which are commonly of shorter duration. Figure 1 shows a flow chart for further data selection. We excluded pregnancies that were terminated through elective caesarean section before 37 weeks of gestation (61 pregnancies in 30 mothers). The primary outcome ‘premature birth’ was defined as delivery before completion of the 37th week of pregnancy. We investigated the effects of different ART regimens on prematurity in several ways. Analysis 1 included all available data, i.e. 1180 pregnancies in 1040 mothers, and

examined the association between prematurity and type click here of ART exposure (no therapy, mono or dual therapy, and cART) without consideration of potential confounding maternal risk factors for prematurity, as such information was commonly incomplete in the early years of the MoCHiV (i.e. in women

exclusively enrolled in the MoCHiV). In analysis 2 we compared rates of premature birth in 418 pregnancies in 366 mothers exclusively on cART, who initiated treatment before or during pregnancy. Analysis 3 was further restricted to 334 pregnancies in 294 women under follow-up in the SHCS during pregnancy. For these women, a detailed treatment history was available, which allowed us to investigate the relationship between the duration of cART, both prior to and during pregnancy, and prematurity or pregnancy duration. The aim Carnitine palmitoyltransferase II of analysis 4 was to control for a number of potential maternal confounders for prematurity and we therefore excluded 762 (of the initial 1180) pregnancies in 695 women who were not under follow-up in the SHCS during pregnancy. We further excluded 43 pregnancies in 41 mothers who did not receive ART during pregnancy and 10 pregnancies in 10 mothers without viral load measurement during pregnancy. The adjusted analysis was based on 365 pregnancies in 318 women. The main outcome was the risk of premature birth, which was analysed using logistic regression with a random effect on mother ID to account for dependence of multiple pregnancies in the same mother. Significance testing was performed using Wald tests.