STRESSFUL LIFE EVENTS AND THE RISK OF UNINTENDED PREGNANCY: IMPLICATIONS FOR TOXIC STRESS AND REPRODUCTIVE HEALTH DISPARITIES DURING ADOLESCENCE AND YOUNG ADULTHOOD

Purpose: 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, p2 SD above the mean was 1.41 times that of women with SLE scores