The Occurrence of Acute Stress and Its Effects on Birth Outcomes

BACKGROUND:  Stressors during pregnancy are associated with increased risk of adverse perinatal outcomes. The Louisiana Pregnancy Risk Assessment Monitoring System (PRAMS) survey contains 13 questions regarding stressors experienced within the year before birth. This analysis investigates the association between these stressors and birth outcomes.

METHODS:  Louisiana resident birth certificate data was linked with Louisiana 2009-2011PRAMS respondent surveys (n=2,971). Multivariable logistic regression accounting for complex survey design was used to examine the association between the 13 stressors and delivering preterm (<37 weeks gestation) or low birth weight (<2500 grams). The stressors were evaluated individually, at least one versus none, the cumulative number of stressors, and grouped based on results of factor analysis representing the stressors’ major constructs. Maternal race, age, and the Kotelchuck index were evaluated as potential confounders in all analyses.  Limitations include 110 surveys missing data on the stressor questions, self-reported data and a <65% response rate.

RESULTS: Within the study period, 11% of births were preterm and 10% were low birth weight. At least one stressor was experienced by 77.4% of Louisiana women and 8.8% experienced six or more stressors. Before adjusting for confounders, no individual stressor, having at least one stressor or cumulative stressors experienced was significantly associated with delivering preterm or low birth weight (p>0.05).  Results did not change after adjusting for confounders (p>0.05). Results of factor analysis indicated four stressor groupings: partner, trauma, financial and emotional. Before adjusting for confounders, having an emotional stressor (family member ill or died) was significantly associated with low birth weight (OR=1.33, 95% CI: 1.00, 1.77), but was not significantly associated after adjusting for confounders (p>0.05). The other three stressor groupings were not significantly associated with delivering preterm or low birth weight, before or after adjusting for confounders.   

CONCLUSIONS:  There was no association between individual stressors, having at least one stressor, cumulative stressors or stressor groupings and delivering preterm or low birth weight after adjusting for confounders. The association reported in the literature between stressors and birth outcomes was not supported using the PRAMS survey questions among Louisiana women. The high prevalence of experiencing at least one stressor within the year before birth suggests the continued need for social support during pregnancy and further need to investigate additional stressor questions that may be more sensitive in demonstrating the reported association.