Sex-ratio at birth in Nigeria: A demographic perspective

Michel Garenne


The study attempts at estimating the sex-ratio at birth in Nigeria. The study focuses on demographic surveys with complete maternity histories, including some 0.50 million births. It compares results with published estimates from births in health facilities and a few data from vital registration, including some 1.13 million births. Results from demographic surveys give an estimate of about 106 boys for 100 girls. There were no significant variations by large region in the country, and no significant trend over the years (1990-2018). Published estimates provided a similar value (106.2), with somewhat lower value in health facilities (105.3), and somewhat higher values in local vital registration (106.8), and major variations among available studies. Despite uncertainty, Nigeria appears to have higher sex-ratios than most African countries, with the exception of Ethiopia, and higher values than its five neighboring countries. Reasons for these high values of the secondary sex-ratio are discussed. (Afr J Reprod Health 2022; 26[4]: 92-97).

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