Infant health consequences of childbearing by teenagers and older mothers.

The association of childbearing at early and late ages with various adverse outcomes of pregnancy was explored in data collected in the 1980 National Natality and Fetal Mortality Surveys. The characteristics of interest for teenage mothers were marital status at conception and the trimester of pregnancy in which prenatal care was begun. For married mothers aged 30 years and older, the variables considered were employment status and occupation during the year preceding childbirth and smoking status before and during pregnancy. The pregnancy outcome variables analyzed were the same for both groups of mothers: fetal loss, low birth weight, and low 1-minute Apgar scores. Although more than half of all births to teenage mothers were to unmarried women, an additional one-quarter of these births were to women who married between the time of conception and the birth of the child. Generally there was little difference in outcomes for teenage mothers who were married at the time of delivery, regardless of their marital status at the time of conception. Pregnancy outcomes for teenagers who did not marry prior to delivery were considerably less favorable. Nearly 90 percent of women aged 30-34 years who had a first birth in 1980 were employed during the year before delivery, an extraordinarily high labor force participation rate. More than half of these employed mothers were in professional occupations, consistent with their very high levels of educational attainment. Although the analysis is limited by the small numbers of births involved, it appears that professionally employed women generally have the best pregnancy outcomes. When mother's smoking status is taken into account,nonsmokers had more favorable outcomes, with births to professionally employed mothers generally most favored.