Psychological and biological markers of stress and bacterial vaginosis in pregnant women.

Objectives: To determine whether stress is associated with risk of bacterial vaginosis (BV) in pregnant women.
Design: Prospective cohort study.
Setting: The prenatal care clinics at the University of North Carolina. The residents' clinic sees mostly government-insured and uninsured women, and the physicians' clinic sees mostly those with private health insurance.
Population: A total of 897 women gave samples for BV analysis. Study participants were 22% African-American, 68% white; 24% unmarried and 44% nulliparous. More than half had completed college.
Methods: Women completed two questionnaires and two interviews reporting stress and psychological aspects of their lives. Measurement scales included the Sarason life events questionnaire, the Cohen perceived stress scale, Spielberger state-trait anxiety, the John Henryism coping style and the Medical Outcomes Study social support inventory. Two stress hormones, corticotrophin-releasing hormone and cortisol, were also measured.
Main Outcome Measures: BV at 15-19 and 24-29 weeks of gestation was diagnosed by Gram's stain.
Results: Women in the highest quartile of stress measures, particularly state anxiety (OR=2.0, 95% CI 1.2-3.3), perceived stress (OR=2.4, 95% CI 1.5-3.9) and total life events (OR=2.0, 95% CI 1.3-3.2), had the highest risk of BV. Adjustment for confounders, especially age, race, and income, reduced these associations (state anxiety: OR=1.3, 95% CI 0.7-2.4; perceived stress: OR=1.4, 95% CI 0.8-2.5; total life events: OR=1.3, 95% CI 0.7-2.4). No clear pattern of association was seen between stress hormones and BV.
Conclusions: Few associations between stress and BV were seen after adjustment for confounders.