A study using data from 40 Demographic and Health Surveys shows that a substantial proportion of women in developing countries continue to marry as adolescents. Overall, 20-50% of women marry or enter a union by age 18, and 40-70% do so by their 20th birthday. Early marriage is most prevalent in Sub-Saharan Africa and in South Asia, and least common in North Africa, the Middle East and Southeast Asia. Women aged 20-24 are less likely to have married by age 20 than are women aged 40-44; the differential is at least 10 percentage points in most countries and reaches 30-40 percentage points in some countries. Education and age at first marriage are strongly associated both at the individual level and at the societal level: A woman who has attended secondary school is considerably less likely to marry during adolescence, and in countries with a higher proportion of women with a secondary education, the proportion of women who marry as adolescents is lower.
(International Family Planning Perspectives, 22:148-157 & 175, 1996)