Brief Report

Half of Urban Teenaged Girls Acquire STDs within 2 Years of First Sexual Activity

Half of urban teenage girls may acquire at least one of three common sexually transmitted diseases (STDs) — chlamydia, gonorrhea, or trichomoniasis — within 2 years of becoming sexually active, according to results of a recent study.1

Researchers at the Indiana University School of Medicine and Regenstrief Institute, both in Indianapolis, followed 381 females enrolled at ages 14-17 in three inner-city adolescent medicine clinics. At enrollment, teens completed a questionnaire and an interview to establish lifetime and recent sexual behaviors, as well as lifetime STD history, and were tested via cervical and vaginal specimens. Study participants returned for follow-up every 3 months for interviews and testing. In alternating quarters, they were instructed to complete daily behavioral diaries and submit weekly self-administered vaginal swabs for STD testing.

By age 15, 25% of the women acquired their first STD, with chlamydia the most common first infection. Depending on the organism, within 4-6 months after treatment of the previous infection, 25% of the women were reinfected with the same organism.

Within 2 years, about 75% of participants with an initial STD were diagnosed with a second infection, although not necessarily of the same type. Within 4 years of an initial infection, 92% of the participants had a subsequent STD.

As a result of their findings, the Indiana researchers call for STI screening in sexually active teenage girls within a year after first intercourse and for retesting of infected females every 3-4 months. Continuing surveillance might be necessary due to the continuing high risk of infection, even if the first rescreening test result is negative.1


  1. Tu W, et al. Time from first intercourse to first sexually transmitted infection diagnosis among adolescent women. Arch Pediatr Adolesc Med 2009;163:1106-1111.