Unintended Pregnancy and the Changing Demography of American Women, 1987-2008

(ProQuest: ... denotes formulae omitted.)1. IntroductionThe persistence of unintended pregnancy in the United States is a major public health concern. Births from unintended conceptions are associated with increased risk of many negative health and social outcomes, independently or because of their association with women's disadvantaged social and economic status (Gipson, Koenig, and Hindin 2008).Since surveillance efforts began about 25 years ago, about half of all U.S. pregnancies have been unintended. Most developed nations report much lower rates in comparison (Singh, Sedgh, and Hussain 2010). In addition, there is a great deal of variation by subgroup (Cubbin et al. 2002; Finer and Henshaw 2006; Finer and Zolna 2011; Forrest and Singh 1990; Forrest 1994; Williams 1991; Koren and Mawn 2010). Women aged 18-24, poor women, unmarried (and particularly cohabiting) women, and women of color report unintended pregnancy rates several times higher than the national rate (Finer and Zolna 2011).Between 1987 and 2008, the U.S. unintended pregnancy rate declined from 59 to 54 per 1,000 women aged 15-44 (Guttmacher Institute 2013). Policymakers who hope to further reduce the unintended pregnancy rate may wish to better understand the factors that have contributed to this small but important decline. Efforts to understand disparities typically involve examining proximate determinants of fertility, specifically the biological and behavioral factors described by the Bongaarts (1978) framework (Forrest and Singh 1990; Forrest 1994; Frost, Singh, and Finer 2007; Schirm et al. 1982). More recent work focuses on the availability of contraceptives, the role of contraceptive use (Frost, Singh, and Finer 2007; Schirm et al. 1982; Westoff 1988), and the role of sexual partners in contraceptive use negotiation (Koren and Mawn 2010; Miller 1986).Research has less frequently explored the impact of changes in population composition on unintended pregnancy rates. For example, less-educated women have higher unintended pregnancy rates than women with more education (Finer and Zolna 2011). If the proportion of the population that is educated were to increase, it is possible that the unintended pregnancy rate could decrease even if reproductive behavior did not change. And in fact, the percentage of women with at least a high school education rose from 59% to 87% between 1970 and 2009, and the percentage of women 19 and older pursuing post-secondary education has also rapidly increased (U.S. Department of Commerce Economics and Statistics Administration & Executive Office of the President Office of Management and Budget 2011). Other shifts in population composition have also occurred. Between 1987 and 2008, the proportion of women 35 and older increased by 13% (U.S. Census Bureau, Population Division 2010). Rates of cohabitation also increased dramatically in the same period (Teachman, Tedrow, and Crowder 2000; Cherlin 2010). Increases in cohabitation began in the 1970s and continue unabated today (Kennedy and Bumpass 2013; Manning 2013). The rise in cohabitation continues to redefine family formation patterns, and unintended pregnancy is particularly high among cohabiting women. Increases in the proportion of women who are cohabiting could lead to an increase in the rate, even if behaviors of cohabiting women do not change.The aim of our paper is to use decomposition techniques to describe the factors underlying the decline in the unintended pregnancy rate from 59 per 1,000 women aged 15-44 in 1987 to 54 in 2008. We examine how the dramatic changes in the educational attainment, marital status, and racial-ethnic composition of American women in the last two decades have affected unintended pregnancy rates.2. Data and methodsWe decomposed the overall rate simultaneously by multiple demographic characteristics, specifically race and ethnicity, relationship status, and educational attainment. For each demographic subgroup, we decomposed the rates to determine what caused the change between two time points. …