Interval between births: United States, 1970-77.
D000293:Adolescent; D000328:Adult; D001741:Black or African American; D001721:Birth Intervals; D001722:Birth Order; D004522:Educational Status; D005260:Female; D005298:Fertility; D005313:Fetal Death; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D008423:Maternal Age; D008875:Middle Aged; D011247:Pregnancy; D012306:Risk; D013223:Statistics as Topic; D014481:United States; D044465:White People