Preconception C. trachomatis seropositivity may up risk of miscarriage

Among women with a history of pregnancy loss, prior exposure to Chlamydia trachomatis poses an increased risk of miscarriage, as reported in a study.

For the study, researchers used data and specimens from the Effects of Aspirin in Gestation and Reproduction study. A total of 1,228 individuals with proven fecundity and a history of 1–2 pregnancy losses were included in the analysis.

Preconception C. trachomatis seropositivity was determined using enzyme-linked immunosorbent assay. Outcome measures included time-to pregnancy (fecundability), live birth status (determined from medical records), and pregnancy loss.

Of the participants, 11 percent had prior exposure to C. trachomatis. In an analysis controlled for baseline demographic and reproductive history variables, C. trachomatis seropositivity was associated with a reduced likelihood of live birth (relative risk [RR], 0.77, 95 percent confidence interval [CI], 0.59–0.99) and a heightened risk of pregnancy loss (RR, 1.16, 95 percent CI, 1.04–1.29). There was no association observed for fecundability (odds ratio, 0.92, 95 percent CI, 0.71–1.20).

In a subset of 50 C. trachomatis-seropositive individuals with chronic inflammation (C-reactive protein levels ≥1.95 but ≤10 mg/L), treatment with low-dose aspirin helped increase live birth rates (RR, 1.68, 95 percent CI, 0.96–2.92) and reduce the risk of pregnancy loss (RR, 0.83, 95 percent CI, 0.65–1.10).

The findings warrant additional studies exploring mechanisms by which C. trachomatis may influence long-term reproductive function in order to identify treatments that can improve outcomes for individuals with a history of infection.