Accumulation of stressful life events and low birth weight: The case of preconception stress and in utero exposure to 9/11

BACKGROUND: It is unknown how the 9/11 attacks affected infant birthweight in the context of preconception stressful life events (PSLEs). This study examined: 1) if and to what extent women's PSLEs moderated the effect of in utero exposure to 9/11 on birthweight; and, 2) if these relationships were stronger closer to the epicenter of the attacks.

METHODS: Data are from the Early Childhood Longitudinal Study – Birth Cohort (ECLS-B), a nationally representative cohort of women who gave birth to a live baby in 2001. We used multinomial logistic regression to examine the interaction between 9/11 and PSLEs on the odds of being born low birth weight (LBW) or very low birth weight (VLBW). We stratified this analysis to examine these relationships in the Northeast.

FINDINGS: We found no effect of 9/11 on infant birthweight; further PSLEs did not moderate the effect of 9/11 on birthweight. However, in the Northeast infants who were exposed in utero to 9/11 and whose mothers who were exposed to PSLEs were more likely to be born LBW (OR=3.23, 95% CI 1.42-7.36) or VLBW (OR=3.60, 95% CI: 1.49-8.74).

CONCLUSIONS: Exposure to PSLEs increased women's vulnerability to 9/11 during pregnancy in the Northeast region of the US. Women close the epicenter of a disaster and who have experienced PSLEs should receive priority services during pregnancy. Because it is difficult to provide services to those in need afterwards, it may be more effective to offer preventive interventions to reduce the deleterious effects of the accumulation of stress.