Preterm prelabour rupture of membranes (PPROM) and pregnancy outcomes in association with HIV-1 infection in KwaZulu-Natal, South Africa

BACKGROUND: SubSaharan Africa has a disproportionate burden of HIV and preterm births (PTB). We hypothesized that PTB in HIV-1 infected women are more likely a result of prelabour rupture of membranes (PROM) and could lead to worse birth outcomes than HIV-uninfected women. We also hypothesized that PPROM increased the risk of mother-to-child transmission (MTCT) of HIV-1. Current clinical management protocols for PPROM do not include a differential treatment plan for HIV-infected women. METHODS: The maternity register at a regional hospital in a high HIV-burden district in South Africa was reviewed to identify all preterm births over a 3 month-period in 2018. We determined the incidence of PPROM using predefined criteria. Maternal age, parity, previous pregnancy complications, antenatal care, body mass index, history of smoking or alcohol, HIV infection and syphilis were computed on chi-square contingency tables to determine risk of PPROM. Overall pregnancy outcomes that included mode of delivery, fetal survival, birth weight, gestational age and newborn apgar scores were compared between HIV-infected and HIV-uninfected women whose pregnancies were complicated by PPROM. HIV-exposed newborns are routinely tested at birth for HIV by PCR. RESULTS: A total of 1758 deliveries were recorded for Jan-Mar, 2018, and 295 (16.8%) were preterm. Maternity charts were retrieved for 236 (80.0%) PTB; 47 of PTB (19.9%; 95%CI 15.0-25.6) were further complicated by PROM which translates to 2.7% (95%CI 1.9-3.4) of all deliveries. None of the risk variables including HIV-positive status (48.9% vs 47.6%) were different between PPROM and non-PPROM groups and the majority of women were receiving cART (94.7 and 92.0%). There were no differences in the proportion of low birth weight (RR 1.2 95%CI 0.6-2.1) or severe preterm birth (RR 1.6; 95%CI 0.9-2.9) between HIV-infected and HIV-uninfected women whose pregnancies were complicated by PPROM. None of the 22 HIV-exposed newborns in the PPROM group were HIV-infected at birth. CONCLUSION: The PPROM incidence is not higher among HIV-infected women and our findings suggest that HIV-infected women who are virally suppressed on cART and presenting with PPROM are less likely to transmit HIV to their infants and do not have worse birth outcomes than HIV-uninfected women.