Individual and community-level determinants of knowledge about fertile periods among women of childbearing age in Tanzania: A multilevel mixed effect analysis of a recent demographic and health survey

Background Knowledge of fertile periods among women of childbearing age remains crucial for reproductive health and family planning globally. Despite its importance, awareness is generally low which contributes to high rates of unintended pregnancies. This study aims to assess the individual and community-level correlates of knowledge about fertile periods among women of childbearing age in Tanzania. Methods An analytical cross-sectional study was conducted using secondary data from the 2022 Tanzania Demographic and Health Survey. Given the survey complex design, a multilevel mixed-effect logistic regression was used to identify determinants of knowledge about fertility periods among women of childbearing age. Adjusted odds ratio (AOR) with corresponding confidence intervals (CI) were computed to estimated strength and magnitude of association. Results Of all women of childbearing age, 22.6% (95%CI: 21.4–23.8), had correct knowledge about fertility period. At the individual level; older age, primary education or higher, living in rich household, parity, media exposure, mobile phone ownership, internet use was significantly associated with fertility knowledge. At the community level women in rural areas and geographical zones associated with fertility knowledge. Conclusion One in five women had correct knowledge about the fertility period. This finding underscores the need for multifaceted approach and context-specific intervention to address individual and community level disparities, aimed at improving maternal health outcomes and fertility goals in Tanzania.