Trends and determinants of changes in cumulative fertility among married women in Kenya between 2003 and 2014: an analysis of demographic health surveys

Abstract Background: Globally, cumulative fertility has declined in the last three decades. In sub-Saharan Africa Including Kenya, this decline started more recent and at a slower pace compared to other regions. Despite a significant fertility decline in Kenya, there are disparities in intra- and interregional fertility. Reduction in cumulative fertility has health benefits for both the mother and child, thus it is important to improve women and children health outcomes associated with high fertility. The study, therefore evaluated the determinants of change in cumulative fertility among married women of reproductive age in Kenya between 2003 and 2014. Methods: The study used the Kenya Demographic and Health Survey (KDHS) datasets of 2003, 2008 and 2014. Analysis of variance (ANOVA) was used to calculate the mean number of children ever born (cumulative fertility) and to assess the change in fertility across different factors. A Poisson-based multivariate decomposition for the nonlinear response model was performed to identify and quantify the contribution of demographic, socioeconomic and reproductive correlates, to the change in cumulative fertility between 2003 and 2014. Results: The study included 3,917, 4,002, and 7,332 weighted samples of women of reproductive age in 2003, 2008, and 2014, respectively. The mean number of children born declined from 3.8 (95% CI: 3.6–3.9) in 2003 to 3.5 (95% CI: 3.4–-3.7) in 2008 and 3.4 (95% CI: 3.3–3.4) in 2014 (p=0.001). The changes in socio-demographic composition of the population (i.e. changes in the characteristics of women) explained 81.6% of the decline while 18.4% was due to changes in fertility behaviour of women. The main contributors to the change in cumulative fertility were reduced child mortality (88.6%), urbanisation (44.5%), education (15.8%), family size (12.8%) and increased age at first marriage (12.1%). Conclusion: The cumulative fertility declined by one-tenth between 2003 and 2014; majorly as a result of the compositional difference in characteristics of women in terms of child death experience, residing in urban areas and level of education. These highlights a need to continue strengthening the healthcare systems (access to quality antenatal care, skilled delivery, and postpartum care) to reduce child mortality and implement education policies that focuses on gender equality and women empowerment.