The rising share of nonmarital births: Fertility choice or marriage behavior?

Adverse Childhood Experiences, Early and Nonmarital Fertility, and Women's Health at Midlife

Adverse childhood experiences (ACEs) have powerful consequences for health and well-being throughout the life course. We draw on evidence that exposure to ACEs shapes developmental processes central to emotional regulation, impulsivity, and the formation of secure intimate ties to posit that ACEs shape the timing and context of childbearing, which in turn partially mediate the well-established effect of ACEs on women's later-life health. Analysis of 25 years of nationally representative panel data from the National Longitudinal Study of Youth (NLSY79; n = 3,893) indicates that adverse childhood experiences predict earlier age at first birth and greater odds of having a nonmarital first birth. Age and marital status at first birth partially mediate the effect of ACEs on women's health at midlife. Implications for public health and family policy aimed at improving maternal and child well-being are discussed.

Race-Ethnic Differences in the Non-marital Fertility Rates in 2006-2010

Research in the 1980s pointed to the lower marriage rates of blacks as an important factor contributing to race differences in non-marital fertility. Our analyses update and extend this prior work to investigate whether cohabitation has become an important contributor to this variation. We use data from the 2006-2010 National Survey of Family Growth (NSFG) and to identify the relative contribution of population composition (i.e. percent sexually active single and percent cohabiting) versus rates (pregnancy rates, post-conception marriage rates) to race-ethnic variation in non-marital fertility rates (N=7,428). We find that the pregnancy rate among single (not cohabiting) women is the biggest contributor to race-ethnic variation in the non-marital fertility rate and that contraceptive use patterns among racial minorities explains the majority of the race-ethnic differences in pregnancy rates.

Nonmarital Fertility, Family Structure, and the Early School Achievement of Young Children from Different Race/Ethnic and Immigration Groups

Working from a life course perspective, this study examined the links between mothers' fertility and relationship statuses and children's early school achievement and how these links varied by race/ethnicity and immigration status. Analyses of nationally representative data from the Early Childhood Longitudinal Study-Kindergarten Cohort revealed that children born to unmarried women scored lower than children of married women on math tests in kindergarten and first grade. This pattern was most attributable to associated differences in family income and parent education, and it was moderated by women's marital and relationship statuses after having their children. Evidence also suggested that the academic risks of some family structure pattern relative to continuously married parents might have been more pronounced for White children.

Decomposing trends in nonmarital fertility among Latinas

CONTEXT

For Latinos, high rates of nonmarital fertility reinforce economic inequality and slow the pace of social and economic incorporation into American society.

METHODS

Changes in the nonmarital fertility ratio--nonmarital births as a percentage of all births (NMFR)--among women aged 15-44 over the period 1994-2005 were partitioned into three components: changes in marital and in nonmarital fertility, and in the proportion of women who were married. Annual birth data were drawn from the national Natality Detail File, and population estimates were drawn from the Current Population Surveys. Analyses were conducted for blacks, whites and Latinas, as well as for selected subgroups of Latinas; differences in NMFRs between racial and ethnic groups were also calculated.

RESULTS

NMFRs were largely unchanged between 1994 and 2002, and then began to rise; they averaged 43% for Latinas, 69% for blacks and 23% for whites over the study period. In 2005, 48% of births to Latinas were nonmarital. Most of the rise in Latinas' NMFR was linked to a decline in marriage. Among foreign-born Latinas, a six-percentage-point increase in the NMFR was due mostly to a rise in nonmarital fertility and a decline in marital fertility, which offset the beneficial effects of a rising marriage rate. The difference between Latinas' and whites' NMFRs was largely attributed to Latinas' higher nonmarital fertility, whereas the difference between blacks' and whites' NMFRs was driven mostly by lower marriage rates among blacks.

CONCLUSIONS

Efforts to reduce out-of-wedlock childbearing among Latinas are needed, and programs should promote healthy marriages, especially among foreign-born Latinas.

The rising share of nonmarital births: is it only compositional effects?

A recent article by Gray, Stockard, and Stone contended that the increase in the proportion of births to unmarried women since 1974 in the United States was not caused by any major change in underlying fertility behavior but rather by a decrease in the proportion of women who are married, which increased both the population at risk and the birth rate of unmarried women relative to that of married women. In this comment, I argue that the statistical test of this explanation used in the article is invalid because the variables in the analysis are not stationary time series. Correct statistical tests reject the explanation. In particular, I demonstrate persistent, nonstationary deviations from the relationships predicted by the theory advanced by Gray et al. For long periods, the proportion unmarried played only a small role in the changes in the ratio of nonmarital to marital birth rates, contrary to the theory.

Composition and decomposition in nonmarital fertility

Ermisch (2009) criticized Gray, Stockard, and Stone (2006), arguing that they incorrectly tested a model positing a nonlinear relationship between the nonmarital fertility ratio and the proportion of unmarried women. I identify a different problem, which is that even if this model were to hold for a particular population, it would not in general hold for subgroups of this population; likewise, were it to hold for subgroups, it would not hold for aggregations of these subgroups.

Comment: there may be compositional effects, but they do not work that way

This analysis joins the debate on how declines in marriage have shifted the composition of the unmarried and married populations in the United States, and how compositional shifts have affected nonmarital birth rates. Gray, Stockard, and Stone (2006) presented one model for compositional effects that Ermisch (2009) challenged with alternative statistical tests. I propose an alternative model for compositional shifts based not on theory but on observed marriage and fertility patterns. The results from this alternative model are consistent with Ermisch's findings yet support Gray et al.'s general case that compositional effects have had an important influence on nonmarital birth rates.

Response to Ermisch, Martin, and Wu

Our recent paper in Demography (Gray, Stockard, and Stone 2006) has attracted the close scrutiny of several prominent academics. Three sets of formal comments, authored independently by Ermisch, Martin, and Wu (EMW), appear in this issue of Demography. In this response we argue that the analysis and evidence of our 2006 paper have withstood the scrutiny of EMW. In particular, we find that a substantial part of the rising share of nonmarital births since 1970 is due to a selection effect associated with marriage. This same selection effect also explains how birth rates could rise in both groups, even though their combined birth rate did not. In sum, though we appreciate the opportunity to expand on several key aspects of our 2006 article, we see no reason to substantially revise any of our major conclusions based on the EMW comments.