Peer-reviewed article
Prevalence of child marriage and its impact on fertility outcomes in 34 sub-Saharan African countries
Sanni Yaya, Emmanuel Kolawole Odusina, Ghose Bishwajit ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study examined child marriage prevalence and its effects on fertility among 60,215 women aged 20-24 years across 34 sub-Saharan African countries using Demographic and Health Survey data from 2008-2017. Overall, 54% of women experienced child marriage (before age 18), with substantial variation across countries, ranging from 16.5% to 81.7%, with Niger, Chad, Guinea, Mali, and Nigeria having the highest rates. Women married before age 18 had significantly higher lifetime fertility (8 times more likely to have 3 or more children), higher pregnancy termination rates, and higher overall childbirth rates compared to those married at 18 or older. The study recommends policies and social programmes to reduce child marriage and improve reproductive health outcomes.
Key points
- Overall prevalence of child marriage in the study population was 54.0%, with large disparities across countries from 16.5% to 81.7%
- Niger (81.7%), Chad (77.9%), Guinea (72.8%), Mali (69.0%) and Nigeria (64.0%) had the highest prevalence of child marriage
- Women married before age 18 were 8.00 times more likely to have 3 or more children in their lifetime compared to women married at age 18 or older
- Women married before age 18 were 1.27 times more likely to have lifetime pregnancy terminations and 5.83 times more likely to experience any childbirth
- Paradoxically, women married before age 18 showed reduced early childbirth (within first year) and reduced rapid repeat childbirth compared to women married at 18 or older
Limitations
The study uses cross-sectional DHS data and cannot establish causation; it measures associations only. The findings reflect retrospective reporting and cannot account for unmeasured confounders or the complex socioeconomic factors that drive both child marriage and fertility outcomes.
Abstract
BACKGROUND: The issue of child marriage is a form of human rights violation among young women mainly in resource-constrained countries. Over the past decades, child marriage has gained attention as a threat to women's health and autonomy. This study explores the prevalence of child marriage among women aged 20-24 years in sub-Saharan Africa countries and examines the association between child marriage and fertility outcomes. METHODS: Latest DHS data from 34 sub-Saharan African countries were used in this study. Sixty thousand two hundred and fifteen women aged 20-24 years were included from the surveys conducted 2008-2017. The outcome variables were childbirth within the first year of marriage (early fertility), first preceding birth interval less than 24 months (rapid repeat of childbirth), unintended pregnancy, lifetime pregnancy termination, the use of modern contraceptive methods, lifetime fertility and any childbirth. The main explanatory variable was child marriage (< 18 years) and the associations between child marriage and fertility outcomes were examined from the ever-married subsample to estimate odds ratios (ORs) and 95% CIs using binary logistic regression models. RESULTS: In the study population, the overall prevalence of women who experience child marriage was 54.0% while results showed large disparities across sub-Saharan African countries ranging from 16.5 to 81.7%. The prominent countries in child marriage were; Niger (81.7%), Chad (77.9%), Guinea (72.8%), Mali (69.0%) and Nigeria (64.0%). Furthermore, women who experience child marriage were 8.00 times as likely to have ≥3 number of children ever born (lifetime fertility), compared to women married at ≥18 years (OR = 8.00; 95%CI: 7.52, 8.46). Women who experience child marriage were 1.13 times as likely to use modern contraceptive methods, compared to adult marriage women (OR = 1.13; 95%CI: 1.09, 1.19). Those who married before the legal age were 1.27 times as likely to have lifetime terminated pregnancy, compared to women married at ≥18 years (OR = 1.27; 95%CI: 1.20, 1.34). Also women married at < 18 years were more likely to experience childbirth, compared to women married later (OR = 5.83; 95%CI: 5.45, 6.24). However, women married at < 18 years had a reduction in early childbirth and a rapid repeat of childbirth respectively. CONCLUSION: Implementing policies and programmmes against child marriage would help to prevent adverse outcomes among women in sub-Saharan Africa. Also, social change programmes on child-marriage would help to reduce child marriage, encourage the use of modern contraceptive, which would minimize lifetime terminated pregnancy and also children ever born.