Effectiveness of theory-based educational interventions on fertility and childbearing intentions: a systematic review and meta-analysis among Iranian populations

Declining fertility highlights the need for theory-based educational interventions that shape couples' childbearing intentions. We examined their effectiveness on fertility and childbearing intentions through a systematic review and meta-analysis. Scopus, Web of Science, PubMed, SID, Magiran and Google Scholar were searched up to 18 August 2025, following PRISMA guidelines, and two reviewers extracted data. Pooled standardised mean differences (SMD) were estimated with random-effects models in Stata; heterogeneity was assessed using I2 and Cochran's Q. Twelve studies (1118 participants) were included. Interventions significantly increased fertility and childbearing intentions (SMD 0.79; 95% CI 0.48 to 1.09; I2 = 88.5%). Effects were significant at short-term (SMD 0.52; 95% CI 0.15 to 0.90) and long-term (SMD 0.96; 95% CI 0.53 to 1.39) follow-up. The Theory of Planned Behaviour showed the largest effect (SMD 1.01; 95% CI 0.55 to 1.48), whereas multimedia education without a theoretical foundation showed no significant effect (SMD 0.05). Interventions of three, five, and eight sessions showed significant effects, whereas two and four sessions did not. Theory-based interventions, especially those grounded in the TPB, were associated with higher fertility intentions among Iranian couples. Culturally adapted programmes may inform policy, although most studies were small, quasi-experimental and relied on self-reported intention.