This study analyzed the roles of trends in sociodemographic factors known to be related to the risk of a teen birth. The goal was to analyze the roles of these trends in maternal education, family structure and mother's age at first birth in the likelihood of adolescents becoming teen mothers across multiple birth cohorts of women covering the years since 1991. Data are from the 1995, 2002, 2006-2010 and 2011-2013 National Surveys of Family Growth (NSFG). Consecutive birth cohorts of female respondents were constructed and retrospectively followed to estimate the risk of a teen birth for each cohort. Logistic regression models estimate the odds of a teen birth across cohorts and within strata of the predictors across cohorts. Maternal education rose across cohorts; the proportion who were non-Hispanic white declined. In general, the likelihood of an adolescent birth did not change within categories of the predictors that are considered at higher risk for a teen birth across birth cohorts. Specifically, there was no change in the odds of a teen birth among women whose mothers did not finish high school, those born to teen mothers and those not from two-parent families. The odds of a birth declined across cohorts for black women. The findings suggest that much of the decline in teen birth rates is due to declines in the proportion of teens in higher risk categories, rather than to declines within those categories.
Keywords: Age at first birth; Birth cohort; Fertility trends; Maternal education; Teen birth.