Risk of pelvic inflammatory disease among u.s. active duty females 12 months following recruit training

BACKGROUND: U.S. military services require annual Chlamydia trachomatis screening for active duty women <26 years, yet only the U.S. Navy, Marines, Coast Guard, and Air Force require additional screening during recruit training. Hence, Army recruits who were asymptomatic upon entry into military service, may not receive treatment for up to 12 months following accession and may therefore be at higher risk for pelvic inflammatory disease (PID). This study will investigate the impact of recruit chlamydia screening policies on PID among U.S. serviceswomen. It was hypothesized that women not screened for chlamydial infection are at higher risk for PID during the 12 months following recruit training compared to women who were screened. METHODS: For this IRB approved retrospective cohort study, the Defense Medical Surveillance System (DMSS) was utilized. Females entering recruit training were followed for 12 months or until a PID diagnosis occurred. The surveillance period was January 1, 2001 to December 21, 2012. Multiple Poisson regression was used to assess the effect of covariates. Hazard analysis was employed to characterize risk over time. RESULTS: Among 304,572 female recruits, there were 5,767 incident diagnoses of PID; 51% occurred among Army servicewomen. Most PID cases (93%) occurred in women <25. The incidence rate was 76% higher in the Army. Risk for Army servicewomen increased after 6 months post-accession. CONCLUSIONS: PID rates were highest in the Army compared to all other services during the 12-months follow-up period. This suggests that recruit chlamydia screening programs contribute to reducing PID incidence in an at-risk female military population.