Objective: This study was done to evaluate the prevalence of chlamydia in late pregnancy after an initial negative test.
Methods: This retrospective cohort study reports prenatal patients entering care between January 1998 and May 2000 at an inner city community based clinic (n = 752). Patients were evaluated if results of initial and late tests (34 weeks gestational age) for chlamydia were known. Charts were abstracted for demographic and pregnancy-related factors. Analysis for categorized data was by chi-squares and odds ratios. Continuous data were analyzed by t-test. Significance was accepted if p < 0.05.
Results: The prevalence of chlamydia was 17.8%, with 3.9% having only the second test positive. Treatment failure and/or reinfection were found in 13.3%. Factors correlated with chlamydial carriage include: age 19 years (p < 0.001), gonorrheal carriage (p < 0.001), lower gravidity (p < 0.01), lower parity (p < 0.05), and never having married (p < 0.001). Logistic regression identified gonorrheal carriage and age 19 years as important for both initial and late chlamydial cervicitis. Marital status was important for initial tests only.
Conclusions: In our high-risk population, repeat testing for chlamydia in late pregnancy was found appropriate.