Perinatal Transmission of HIV and Effectiveness of Prevention of Mother-to-Child Transmission Programme in Oyo State

Despite significant global progress, mother-to-child transmission of HIV remains a preventable cause of paediatric HIV infection in Nigeria, with programme effectiveness varying considerably by state and health system capacity. This study evaluates the effectiveness of the prevention of mother-to-child transmission (PMTCT) programme and residual perinatal transmission rates in Oyo State, South West Nigeria. A retrospective cohort design reviewed records of 300 HIV-positive pregnant women who enrolled in PMTCT services at University College Hospital and two other public hospitals in Oyo State between 2019 and 2022. Programme effectiveness indicators included antiretroviral therapy (ART) initiation at first antenatal contact, viral load suppression at delivery, adherence to infant nevirapine prophylaxis, early infant diagnosis uptake at 6 weeks, and final infant HIV status at 18 months. ART was initiated in 94 percent of enrolled women. Viral load suppression at delivery was documented in 71 percent. Early infant diagnosis coverage was 78 percent. Final HIV-positive status was confirmed in 3.8 percent of tested infants at 18 months, primarily among women with detectable viral load at delivery. Late booking and loss to follow-up between deliveries and postnatal contact were the primary programme leakage points. Recommendations include community-based viral load monitoring, peer support group linkage, and defaulter tracing systems to close PMTCT programme gaps in Oyo State. Keywords: PMTCT, HIV, mother-to-child transmission, Oyo State, antiretroviral therapy