Decomposing the effect of women's educational status on fertility across the six geo-political zones in Nigeria: 2003–2018

Background: Nigeria faces a dual challenge of high fertility rates and limited female education. Studies suggest that education can contribute to fertility reduction. This study aimed to show the differences and quantify the disparity in fertility rates between educated and uneducated women in Nigeria. Methods: A repeated cross-sectional analysis was conducted using secondary data from the Nigeria Demographic and Health Surveys (2003, 2008, 2013, 2018; Total = 121,774). Fertility differentials for women aged 15–49 were measured using Oaxaca-Blinder decomposition (α = 0.05). Results: The proportion of women without education remained high throughout the study period (41.6% in 2003, 35.8% in 2008, 37.8% in 2013 and 34.9% in 2018). Uneducated women consistently exhibited higher fertility rates than educated women across all survey years and regions. The risk difference of high fertility was greatest in the SouthEast region (34.0) and lowest in the North East (22.19). Factors contributing to the disparity included maternal age, age at first marriage, wealth index, and age at first birth. Conclusion: Marked fertility inequalities exist between educated and uneducated women across Nigerian regions. These findings highlight the crucial role of female education in fertility reduction efforts.