Racial Disparities and the Effect of Maternal Sexually Transmitted Infections on Adverse Birth Outcomes

Background: Understanding the role of sexually transmitted infections (STIs) in disparities associated with adverse birth outcomes (ABOs) may help target specific interventions for black and white women. Despite extensive research existing on racial disparities in ABOs and STIs, a gap in the literature exists regarding disparities in the association between STIs and ABOs. Methods: This cross-sectional study utilizes data from Missouri vital statistics (n=173,624), years 2010-2012. Exposure was classified as: primary-HIV, either alone or with another STI (gonorrhea, syphilis, hepatitis B, or hepatitis C); secondary-aforementioned STIs without HIV; and unexposed. Outcomes of interest included preterm birth (birth prior to 37 weeks of gestation), low birth weight (less than 2500g), and small for gestational age (weight below the 10th percentile for gestational age). Bivariate and multivariate logistic regression models estimated risk of STIs on ABOs and adjusted for potential confounders (age, education, marital status, prenatal care, health insurance, previous preterm birth, smoking, BMI, weight gain, and chronic health conditions), by calculating odds ratios and 95% confidence intervals for primary and secondary exposures on all three outcomes. Results: HIV exposure was significantly associated with a 72% increased odds (OR: 1.72, 95% CI: 1.03-2.89) for having a low birth weight birth and a 71% increased odds (OR: 1.71, 95% CI: 1.03-2.84) for being small for gestational age, when compared with women without an STI, after adjusting for potential confounding variables. Race was not an effect modifier. Conclusions: Reducing one's risk of having an STI before pregnancy provides an important primary prevention tactic that can reduce risks for ABOs should one become pregnant.