Chlamydia Trachomatis and the Development of Preeclampsia in Pregnancy

Abstract Background: Preeclampsia is a major contributor to maternal and perinatal morbidity and mortality. While known risk factors include chronic hypertension, diabetes, and autoimmune disease, emerging evidence suggests a potential association between Chlamydia trachomatis infection and hypertensive disorders of pregnancy. Objective: To evaluate whether Chlamydia trachomatis infection is associated with an increased risk of preeclampsia. Methods: This retrospective cohort study utilized data from the TriNetX Research Network. Pregnant individuals with and without prior Chlamydia trachomatis infection were identified using ICD-10 codes. Propensity score matching was used to balance cohorts on race, comorbidities, and socioeconomic factors. Outcomes were analyzed using risk difference, risk ratio, odds ratio, Kaplan Meier survival curves, and t-tests. Results: Women with a history of Chlamydia infection had a slightly higher incidence of preeclampsia (3.6% vs 3.5%). The risk difference was 0.001 (95% CI, 0.000-0.003; P=0.042); risk ratio, 1.037; odds ratio, 1.038. Survival analysis showed no significant difference in time to onset (P=0.164). However, women in the Chlamydia group experienced a significantly higher mean number of preeclampsia events (4.43 vs 2.81; P<0.001). Conclusion: Although the increased risk is modest, Chlamydia trachomatis infection may contribute to the development of preeclampsia through inflammatory endothelial pathways. Universal STI screening during pregnancy, particularly in high-risk populations, may offer an opportunity for early intervention and improved maternal outcomes.