Objective: To determine the frequency and patterns of recurrent Chlamydia trachomatis infections, the most common bacterial sexually transmitted infection in young women.
Design: Cohort study using different data collection methods, including face-to-face interviews, medical record reviews, urine-based screening for C trachomatis infections, and a review of state health department reports of C trachomatis diagnoses.
Setting: Ten community-based health centers that provided reproductive health care from June 1998 to September 2001.
Participants: Eligibility criteria included being nulliparous, between the ages of 14 and 19 years, and human immunodeficiency virus-negative, all at the time of recruitment. This convenience sample (N = 411) was recruited by word of mouth, clinician referrals, and advertisements in the clinics. Prospective follow-up data were available for 93.9% (386/411) of the sample. The exposure of interest was prior chlamydia infection. Main Outcome Measure Diagnosis of recurrent C trachomatis infection.
Results: During the follow-up period of 23 318 person-months (mean, 4.7 years per person), 216 participants (52.6%) were diagnosed as having C trachomatis infection, and 123 participants (29.9% of the total sample and 56.9% of those with initial infections) were diagnosed as having recurrent C trachomatis infections. Of 456 C trachomatis diagnoses made during the study period, 241 (52.9%) were recurrent infections. The rate of recurrent infections was 42.1 per 1000 person-months. The median time to recurrent infection was 5.2 months.
Conclusion: Recurrent C trachomatis infections comprise a substantial health burden among young women, possibly higher than previously recognized in this vulnerable population.