Contraceptive Method Use and Chlamydia Positivity Among California Family Planning Clients: The Case for New Multipurpose Prevention Technologies

Adolescent girls and young women experience high rates of sexually transmitted infection (STI) with currently available contraceptive methods, yet few studies examine the burden of chlamydial infection by contraceptive method used. In this cross-sectional analysis, we linked July 2012-June 2013 claims from a publicly-funded family planning program in California to chlamydia laboratory test results. Female clients were classified by the most effective contraceptive method reported by providers during the year: tier 1 (high-efficacy permanent or long-acting reversible methods), tier 2 (shorter-acting hormonal methods), or tier 3 (barrier methods, emergency contraception, or natural family planning). In addition, we identified clients who received condoms from providers. We used log-binomial models to estimate adjusted prevalence ratios comparing chlamydia positivity by contraceptive method(s). Of 74,636 female clients of ages 15-29 years with chlamydia test results, 5.1% had at least one positive test during the year. Chlamydia positivity was highest among tier 2 users (5.3%) compared with 4.5% and 4.9% among tiers 1 and 3 users, respectively (p