Repeat pregnancies among metropolitan-area teenagers: 1971-1979.

A declining proportion of young women who become premaritally pregnant marry during their first pregnancy: Thirty-three percent of metropolitan-area women aged 15-19 interviewed in 1971 did so, compared to 16 percent of those interviewed in 1979. At the same time, those who do marry have a high probability of conceiving again within 24 months of the outcome of the first pregnancy: Of those surveyed in 1979, almost 50 percent did so, up from 15 percent in 1976. While a number of factors may account for the high rate of second pregnancies among married teenagers, it apparently results from less use, or less efficient use, of contraceptives. Among teenagers who experienced a premarital pregnancy and remained single, most age, race and pregnancy subgroups showed either no change in the cumulative risk of a second pregnancy within 24 months or a decline in that risk between 1976 and 1979. The most notable decline was among young women whose first pregnancy ended in abortion; an increasing proportion of premaritally pregnant women, especially those who do not marry, are included in this group. White teenagers show a small increase in the risk of a premarital second pregnancy--an exception to the decline generally noted in second pregnancies among young women who do not marry. The increase parallels rises in the proportions of those who do not use contraceptives and of those who use less effective methods following the premarital first pregnancy. The apparent increase between 1976 and 1979 in the risk of a second pregnancy both among whites who married during the first pregnancy and among those who did not is in contrast to a decrease in risk for those two groups between 1971 and 1976. Although 1979 data are not available for nonmetropolitan-area women, a comparison of second pregnancies in 1971 and 1976 indicates that the decline in risk of a second pregnancy was greater for nonmetropolitan women than for metropolitan women.