Sexually transmitted infections and adverse birth and infant outcomes among pregnant women in rural southern India

Introduction: Sexually Transmitted Infections (STIs) in pregnancy have been reported to be associated with adverse birth and infant outcomes. Aim: To examine the relationship between adverse birth outcomes and select STIs in a cohort of pregnant women in rural Southern India, using stored vaginal samples. Materials and Methods: Pregnant women with (n=208) and without (n=213) adverse birth outcomes were matched on women’s age and parity. Adverse birth or infant outcomes were defined as newborns that weighed less than 2.5 kilograms, were delivered before 37 weeks of gestation, or were stillborn, died, or admitted to an intensive care unit at birth. Those women were compared to pregnant women who delivered a full-term baby that had normal birthweight. A one-tailed prevalence ratio was calculated. Mean cycle threshold values were compared between symptomatic and asymptomatic women with Trichomonas Vaginalis (TV) infection. Results: Among the 208 women with adverse birth outcomes, 22 (10.6%) tested positive for any STI: 15 (7.2%) tested positive for TV, 1 (0.5%) for Chlamydia Trachomatis (CT), 1 (0.5%) for Neisseria Gonorrhoeae (NG), 2 (1.0%) for Human Immunodeficiency Virus (HIV), and 3 (1.4%) for Hepatitis B. Among 213 women with normal birth outcomes, 14 (6.6%) tested positive for any STI, 12 (5.6%) tested positive for only TV monoinfection, 1 (0.5%) for NG monoinfection, 1 (0.5%) for every tested STI, i.e., TV, CT, and NG. In the present study, we found that women with adverse birth outcomes had a higher ratio of STIs than those without adverse birth outcomes (prevalence ratio of 1.7 {95% CI: 0.9-3.3]}. Among women who tested positive for any STI with or without adverse birth outcomes, 67.7% were asymptomatic. Among pregnant women that tested positive for TV infection, there was no difference between mean cycle threshold values between symptomatic and asymptomatic women. Conclusion: Adverse birth outcomes were more common among women with STIs. Nucleic acid amplification testing identified modest numbers of STIs among pregnant women. Many women with positive nucleic acid amplification tests were not treated for infections because they were asymptomatic.