Stressful life events and the risk of unintended pregnancy: Implications for toxic stress and reproductive health disparities during adolescence and young adulthood


Hall, Kelli Stidham; Beauregard, Jennifer L.; Livingston, Melvin D.; & Harris, Kathleen Mullan (2019). Stressful life events and the risk of unintended pregnancy: Implications for toxic stress and reproductive health disparities during adolescence and young adulthood. Psychological Well-Being: International Transcultural Perspectives. Washington, DC: Journal of Adolescent Health.


Stressful life events (SLEs) experienced during childhood and adolescence are of particular concern given their potential to alter critical bio-psycho-social developmental processes, subsequently contributing to toxic stress and its long-term physical, mental, and social consequences. Socially disadvantaged groups, such as minority and poor young women, are particularly vulnerable to toxic stress; stress is a direct contributor to health disparities. However, studies to date on mental and reproductive health have seldom investigated the complex social context of stress or chronic stress exposure using life course perspectives. We prospectively analyzed the effects of SLEs on risk of first pregnancies reported as unintended among a nationally-representative cohort of young U.S. women followed over 15 years. We also tested differential SLE effects on pregnancy risk by race/ethnicity and socioeconomic status. Methods Data were drawn from 8,810 adolescent and young adult women followed over four waves (1994-2009) in the National Longitudinal Study of Adolescent to Adult Health. We employed items measuring over 40 different developmentally-relevant SLEs to create a standardized time-varying additive index score for SLEs at each wave. We estimated the effects of SLE scores (wave X) on time to unintended first pregnancy (wave X+1) using adjusted Cox proportional hazard models, where person-months since study entry was the time scale and censoring women after their first pregnancy. We stratified models by race/ethnicity and parental income level at wave I. Results Among all women, a 1-standard deviation increase in SLE scores was associated with an increased risk of unintended pregnancy (aHR 1.11, 95% CI=1.04-1.17, p<0.01); the pregnancy risk for women with SLE scores >2 SD above the mean was 1.41 times that of women with SLE scores <1 SD above the mean (aHR = 1.41, 95% CI 1.14-1.76, p<0.01). In stratified models, effects of SLE scores on unintended pregnancy risk varied across racial/ethnic and socioeconomic groups and according to various elevated SLE thresholds. For example, all SLE indicators were associated with unintended pregnancy for White women, whereas a 1 SD increase in SLE score or having an SLE score 1-2 SD above mean (but not >2 SD, compared with <1 SD) were associated with unintended pregnancy for Black women. SLE scores were associated with unintended pregnancy for women at the lowest ($0-19,999) and highest ($>75,000) income levels (1 SD increase: aHR 1.21, 95% CI: 1.03-1.23, p<0.01 and aHR 1.36, 95% CI: 1.12-1.66, p<0.01, respectively). Conclusions Higher levels of social stress exposure were associated with unintended pregnancy among young women in this large, longitudinal, population-based cohort study. Moreover, varying levels of SLEs appeared to relate to pregnancy risk differently for different sub-groups of women, such that for some increasingly high exposure levels placed them at risk for pregnancy (e.g. White and high-income women) whereas small incremental or lower plateauing levels of SLE exposure were riskiest for other groups (e.g. Black and low-income women). Reproductive public health efforts that consider toxic stress and its social context, perhaps harnessing trauma-informed care approaches, are needed to more effectively concurrently address mental and reproductive health during adolescence and young adulthood.


Reference Type

Conference proceeding

Book Title

Psychological Well-Being: International Transcultural Perspectives


Hall, Kelli Stidham
Beauregard, Jennifer L.
Livingston, Melvin D.
Harris, Kathleen Mullan

Year Published


Volume Number





Journal of Adolescent Health

City of Publication

Washington, DC





Reference ID