Psychosocial stressors and low birthweight in an urban population

Low birthweight is a major determinant of infant mortality, as well as a contributor to infant and childhood morbidity. A key issue is how to reduce the incidence of low birthweight in the United States. One emerging factor is exposure to psychosocial stressors. In this research, we evaluated the association between exposure to psychosocial stressors and low birthweight in a population of urban, low-income pregnant women.

Over 2,000 pregnant women 18 years of age and older were enrolled in this prospective study and recruited at their first prenatal care visit. We obtained information on maternal exposure to stressors. After the pregnancy, we abstracted clinical records of each woman enrolled in the study. Logistic regression was used to estimate the adjusted odds ratio for the association between stressor group membership and low birthweight, controlling for the effects of confounding factors.

In logistic regression analyses stratified by race, for African-American women, the following variables were significantly associated with low birthweight: smoking, hypertension, low prepregnancy weight, hospitalization during pregnancy, previous preterm birth, and exposure to stressors. For Caucasian women, significant predictors were: smoking, drug use, hospitalization during pregnancy, hypertension, and previous preterm birth. Exposure to stressors was also significantly associated with many clinical and behavioral risks for low birthweight.

Our results suggest two potential mechanisms for an association between stressors and low birthweight. Exposure to stressors may be indirectly associated with low birthweight through a relationship with clinical and behavioral risks for low birthweight. Exposure to psychosocial stressors may also be directly associated with risk of low birthweight among African-American women.