A study using data from 40 Demographic and Health Surveys shows that a
substantial proportion of women in developing countries continue to m
arry as adolescents. Overall, 20-50% of women marry or enter a union b
y age 18, and 40-70% do so by their 20th birthday. Early marriage is m
ost prevalent in Sub-Saharan Africa and in South Asia, and least commo
n in North Africa, the Middle East and Southeast Asia. Women aged 20-2
4 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 a
nd reaches 30-40 percentage points in some countries. Education and ag
e at first marriage are strongly associated both at the individual lev
el and at the societal level: A woman who has attended secondary schoo
l is considerably less likely to marry during adolescence, and in coun
tries with a higher proportion of women with a secondary education, th
e proportion of women who marry as adolescents is lower.