In 2023, one‐fourth of new HIV acquisitions in children globally resulted from vertical transmission following incident HIV during pregnancy or breastfeeding. Oral pre‐exposure prophylaxis (PrEP) with tenofovir disoproxil and emtricitabine is safe and effective in pregnancy and postpartum, with long‐acting options emerging. Integrating PrEP into antenatal and postnatal care (ANC/PNC) is a crucial person‐centred approach to prevent maternal HIV acquisition and vertical transmission. This review summarizes oral PrEP initiation, continuation and adherence among pregnant and postpartum women receiving ANC/PNC. We systematically searched three databases for English‐language quantitative studies published between 1 January 2015 and 28 March 2024. Eligible studies focused on pregnant and/or postpartum women accessing PrEP through ANC/PNC, and reported on initiation (receipt of prescription or self‐reported use), continuation (persistent use over time) and/or adherence (self‐reported and/or objective). We identified 481 articles; 12 studies from Kenya, Lesotho, Malawi and South Africa met our inclusion criteria. Study heterogeneity (e.g. definitions used, population included, follow‐up time) precluded meta‐analysis. All studies enrolled pregnant women; three also enrolled postpartum women. Median gestational age at enrolment ranged from 20 to 26 weeks, and follow‐up periods from 1 month post‐enrolment to 12 months postpartum. Oral PrEP initiation ranged from 14% to 84%. Continuation at 3 months ranged from 22% to 90% and declined postpartum in all studies. Self‐reported adherence (daily use) ranged from 11% to 81% in the past 7 or 30 days at 1 month (four studies) and from 54% to 81% at 3 months (two studies). Objectively measured adherence ranged from 34% to 62% for detectable tenofovir or tenofovir diphosphate levels at 1 month (three studies). One Kenyan trial demonstrated that universal versus risk‐based offers of oral PrEP resulted in similar PrEP use and HIV incidence. Two‐way SMS communication (Kenya) and real‐time adherence biofeedback counselling using urine tenofovir testing (South Africa) enhanced PrEP continuation/adherence compared to standard‐of‐care.