Timing of maternal antiretroviral therapy initiation and HIV status of children at 18 months in Ibadan, Nigeria

High rates of mother-to-child transmission (MTCT) of Human immunodeficiency virus (HIV) exist in Nigeria, despite the progress in scaling up antiretroviral therapy (ART) for pregnant women living with HIV. Studies have shown that the risk of MTCT is lowest when ART is initiated before pregnancy or during the first trimester, and a delay in ART initiation can increase the risk of MTCT. Investigating the relationship between the mother’s timing of ART and the HIV status of their child at 18 months will help facilitate policies that will promote timely ART uptake. Thus, this study examined the relationship between the mother’s timing of ART initiation and the HIV status of the child at 18 months in Ibadan Metropolis, Nigeria. This study analysed a retrospective cohort data of 610 women living with HIV and 611 of their children extracted from the National PMTCT Maternal Cohort Register (NPMCR) and the National PMTCT Child Follow-up Register (NPCFR) of four selected HIV treatment centres in Ibadan metropolis, Oyo State. Descriptive statistics were used to describe the characteristics of the mothers and children. Chi-square tests and logistic regression were used to assess the relationship between mothers’ age, education, viral load before and at delivery, timing of ART initiation, child sex, and birth weight with the child’s HIV status at 18 months. The level of significance was set at α = 0.05. The mean age of mothers in the study was 37.82 (± 10.38years). Only 11.6% of the mothers had completed tertiary education. About 51.4% of the children were male. Of the 611 HIV-exposed infants in this study, 4.8% were HIV-positive after 18 months. About 81.7% of mothers started ART before conception, 12.9% started ART after conception, and 3.4% started ART at delivery or post-delivery. Maternal viral load before delivery was significantly associated with the child’s HIV status at 18 months. Mothers with unsuppressed viral load had the highest proportion of HIV-positive children (7.5%), compared with only 2.6% among mothers whose viral load was suppressed (P-value = 0.04). Mothers initiating ART before pregnancy had lower odds of an HIV-positive child after 18 months compared to those who initiated ART after birth (AOR 0.018, 95% CI 0.003–0.13), p-value (< 0.001). A relationship exists between the mother’s timing of ART and the HIV status of their child at 18 months. Early initiation of ART before conception significantly reduced HIV infection at 18 months. Strengthening pre-conception care and integrating HIV testing into reproductive health services are critical to sustain these gains. Not applicable.