Patterns of caesarean section in HIV infected and non-infected women in Malawi: is caesarean section used for PMTCT?

Lyson Tenthani, Joep J. van Oosterhout, Andreas D. Haas, Malango Msukwa, Nozgechi Phiri, Frank Chimbwandira, Kali Tal, Karoline Aebi-Popp, Janne Estill, Olivia Keiser

Caesarean section (CS) is not recommended for PMTCT in Malawi HIV Guidelines, contrary to most high-income countries where CS is indicated if viral suppression is sub-optimal pre-delivery. We describe patterns of CS in HIV-infected and uninfected women in Malawi and explored if insight into the use of Elective CS (ECS) for PMTCT could be obtained. We used routinely collected data from individual medical records from 17 large health facilities in the central and southern regions of Malawi, from January 2010 to December 2013. We included data from maternity registers from all HIV-positive women, and randomly selected around every fourth woman with negative or unknown HIV status. We used multivariable logistic regressions and cluster-based robust standard errors to examine independent associations of patient- and facility characteristics with CS and ECS. We included 62,033 women in the analysis. The weighted percentage of women who had a spontaneous vaginal delivery was 80.0% (CI 95% 79.5-80.4%); 2.4% (95% CI 2.3-2.6%) had a vacuum extraction; 2.3% (95% CI 2.2-2.5%) had a vaginal breech delivery; 14.0% (95% CI 13.6-14.4%) had a CS while for 1.3% (95% CI 1.2-1.4%) the mode of delivery was not recorded. Prevalence of CS without recorded medical or obstetric indication (ECS) was 5.1%, (n = 3152). Presence of maternal and infant complications and older age were independently associated with CS delivery. HIV-positive women were less likely to have ECS than HIV negative women (aOR 0.65; 95%-CI 0.57-0.74). Among HIV-positive women, those on antiretrovirals (ARV's) for ≥4 weeks prior to delivery were less likely to have ECS than HIV-positive women who had not received ARVs during pregnancy (aOR 0.81; 95% CI 0.68-0.96). The pattern of CS's in Malawi is largely determined by maternal and infant complications. Positive HIV status was negatively associated with CS delivery, possibly because health care workers were concerned about the risk of occupational HIV transmission and the known increased risk of post-operative complications. Our results leave open the possibility that CS is practiced to prevent MTCT given that ECS was more common among women at high risk of MTCT due to no or short exposure to ARV's.