Abstract
Pre-eclampsia is a hypertensive disorder of pregnancy constituting a leading cause of maternal and perinatal morbidity and mortality globally, with a disproportionate burden in low- and middle-income countries. Primary Health Care (PHC) centres are critical first-contact points for antenatal care in underserved communities, yet the determinants of pre-eclampsia among PHC attendees remain inadequately synthesized. The review aimed to synthesize the existing evidence on the prevalence and determinants of pre-eclampsia among pregnant women, with particular focus on factors identifiable at the PHC level in Nigeria and Osun State context. The study is a systematic review, which was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. Comprehensive searches were performed across PubMed/MEDLINE, Google Scholar, Scopus, African Journals Online (AJOL), and the Cochrane Library for studies published between January 2013 and March 2026. Observational studies (cross-sectional, case-control, and cohort designs) reporting prevalence estimates and/or determinants of pre-eclampsia among antenatal clinic attendees were included. Quality assessment was performed using the Newcastle-Ottawa Scale (NOS) adapted for cross-sectional studies. Narrative synthesis with thematic categorization of determinants was employed. The results revealed that 42 studies met the inclusion criteria and were included in the final synthesis.. The global pooled prevalence of pre-eclampsia was 4.43%, with significantly higher estimates in Sub- Saharan Africa (6.1–13%) and in Nigerian PHC/facility-based settings (4.51–18.9%). Six thematic domains of determinants emerged: biomedical/maternal health factors (obesity, chronic hypertension, diabetes, previous pre-eclampsia history), obstetric factors (nulliparity, multiple gestation, advanced maternal age), lifestyle factors (physical inactivity, poor dietary patterns, high salt intake), socioeconomic factors (low education, low income, financial barriers to care), health system/ANC utilization factors (late booking, inadequate ANC visits, limited screening capacity), and awareness/knowledge factors (pervasive poor knowledge across settings). Previous pre-eclampsia history was consistently the strongest predictor (OR range: 7–21.5), followed by chronic hypertension (OR: 2–18.7) and obesity (OR: 2.5–3.7). Social determinants including education and socioeconomic status were confirmed as essential but frequently overlooked in clinical risk assessments. In conclusion, the determinants of pre-eclampsia are multifactorial, spanning biomedical, obstetric, lifestyle, socioeconomic, and health system domains. PHC-level interventions including strengthened screening, structured health education, early ANC booking promotion, and social determinant-responsive care are critical for reducing the burden, particularly in underserved settings such as Ede South LGA, Osun State.