Impact of High-Risk Fertility Behaviour on Under-five Mortality in Asia and Africa: Evidence from Demographic and Health Surveys

Abstract

Background: Younger or older maternal age, short inter-pregnancy birth interval, and higher birth order of the child are considered to be high-risk fertility behaviour (HRFB). Under-five mortality being disproportionately concentrated in Asia and Africa, this study analyses the association between HRFB and under-five mortality in selected Asian and African countries.Methods: This study used Integrated Public Microdata Series-Demographic and Health Surveys (IPUMS-DHS) data from 32 countries in Sub-Saharan Africa, Middle East, North Africa, and South Asia from 1986 to 2017 (N=1,467,728). Previous evidence hints at four markers of HRFB: women’s age at the birth of index child <18 years or >34 years, short preceding birth interval (PBI) <24 months, and child’s birth order >3. Using logistic regression, we analysed the change in the odds of under-five mortality as a result of i) exposure to HRFB individually, ii) exposure to any single HRFB risk factor, iii) exposure to multiple HRFB risk factors, and iv) exposure to specific combinations of HRFB risk factors. Results: Mother’s age at the birth of index child <18 years and preceding birth interval (PBI) <24 months were significant risk factors of under-five mortality, while a child’s birth order >3 was a protective factor against under-five mortality. Presence of any single HRFB was associated with 1.067 times higher risk of under-five mortality (OR = 1.067; 95% CI: 1.042 - 1.090; P < 0.001). Presence of multiple HRFBs was associated with 1.392 times higher risk of under-five mortality (OR = 1.392; 95% CI: 1.355 - 1.431; P < 0.001). Some specific combinations of risky fertility behaviour such as younger maternal age (<18 years) and short preceding birth interval (PBI <24) significantly increased the odds of under-five mortality.Conclusion: Younger maternal age and short preceding birth interval significantly increase the risk of under-five mortality. This highlights the need for effective legislation to curb child marriages and increased public investment in reproductive healthcare with a focus on higher contraceptive use for an optimal interpregnancy interval.