Child marriage (before 18 years) is prevalent in Pakistan, which disproportionately affects young girls in rural, low income and low education households. Our study aims to determine the association between early marriage and high fertility and poor fertility health indicators among young women in Pakistan beyond those attributed to social vulnerabilities. Nationally representative data from Pakistan Demographic and Health Survey, 2006-2007, a cross-sectional observational survey, were limited to ever-married women aged 20-24 years (n = 1,560; 15 % of 10,023) to identify differences in poor fertility outcomes [high fertility (three or more childbirths); rapid repeat childbirth (<24 months between births); unwanted pregnancy (any ever); pregnancy termination (any stillbirth, miscarriage or abortion ever)] by early (<18) versus adult (≥18) age at marriage. Associations between child marriage and fertility outcomes were assessed by calculating adjusted odds ratios (AORs) using logistic regression models after controlling for demographics, social equity indicators (education, wealth index, rural residence), contraception use, marriage duration and culture-specific factors (husband's desire for more children, son preference). Overall, 50 % of ever-married women aged 20-24 years in Pakistan were married before the age of 18 years. Girl child marriage was significantly (p < 0.001) associated with low social equity indicators (poverty, rural residence, and no formal education). Adjusted logistic regression models showed that girl child marriage was significantly associated with high fertility (AOR 6.62; 95 % CI 3.53-12.43), rapid repeat childbirth (AOR 2.88; 95 % CI 1.83-4.54), unwanted pregnancy (AOR 2.90; 95 % CI 1.75-4.79), and pregnancy termination (AOR 1.75; 95 % CI 1.10-2.78). Girl child marriage affects half of all ever-married women aged 20-24 years in Pakistan, and increases their risk for high fertility and poor fertility health indicators, highlighting the need of increasing the age of marriage among women in Pakistan. Efforts to eliminate girl child marriage by strict law enforcement, promoting civil, sexual and reproductive health rights for women can help eliminate girl child marriage in Pakistan.
- Child marriage