Abstract
Nigeria has one of the highest adolescent fertility rates globally, yet evidence on secondary school students’ knowledge and attitudes toward teenage pregnancy remains fragmented. This study aimed to estimate the pooled prevalence of good knowledge and positive attitude toward teenage pregnancy among Nigerian secondary school students and to identify key sources of heterogeneity. A systematic review and metaanalysis of school-based cross-sectional studies published between (February 2018 to December 2025) was conducted. PubMed, African Journals Online, Google Scholar, and major Nigerian institutional repositories were searched. Eligible studies involved secondary school students in Nigeria and reported quantitative data on knowledge and/or attitudes toward teenage pregnancy. Study quality was assessed using the Joanna Briggs Institute checklist, and a random-effects model was applied to pool prevalence estimates and odds ratios. Thirty-one studies comprising 22,164 students from 19 states met the inclusion criteria. The pooled prevalence of good knowledge of teenage pregnancy was 53.8% (95% CI: 47.2–60.3%; I² = 99.1%; 31 studies). The pooled prevalence of positive attitude operationalised as perceiving teenage pregnancy as unacceptable and/or preventable was 62.7% (95% CI: 56.4–68.7%; I² = 98.7%; 28 studies). Subgroup analyses showed markedly lower knowledge in rural compared with urban schools (46.3% vs 67.8%, p < 0.001) and in northern compared with southern Nigeria (41.2% vs 64.5%, p < 0.001). Female students were significantly more likely to have good knowledge than males (OR = 1.56, 95% CI: 1.38–1.77), but demonstrated only slightly more supportive attitudes toward pregnant peers. Across studies, peers (64.3%) and social media (61.8%) were the dominant information sources, followed by teachers (43.2%), while parents contributed minimally (17.9%). Overall, more than four in ten students lack adequate knowledge of teenage pregnancy and stigmatizing attitudes remain widespread, particularly in rural and northern settings. Scaling up context-appropriate, rights-based comprehensive sexuality education with a deliberate focus on underserved groups, alongside stronger engagement of parents and teachers, is urgently required to reduce teenage pregnancy and its consequences in Nigeria.