December 11, 2002
University of California-San Francisco researchers worked with physicians at 10 Kaiser Permanente managed care pediatric clinics in Northern California from April 2000 to March 2002. They found that routine screening revealed that 5.8 percent of sexually active girls ages 14-18 -- who otherwise would not have been tested -- were positive for chlamydia. That rate is on track with the 6 percent to 9 percent national infection rate found in routine screening, CDC reports.
Chlamydia is the most common bacterial STD in the United States, with about 3 million new cases annually. Teenage girls are six times more likely to contract it than adult women. Because more than 75 percent of cases have no symptoms, many teens do not discover they are infected until they try to get pregnant years later, said lead author Dr. Mary-Ann Shafer, associate director of adolescent medicine at UCSF. The full report, "Effect of a Clinical Practice Improvement Intervention on Chlamydia Screening Among Adolescent Girls," is published in today's Journal of the American Medical Association (2002;288:2846-2852).
The new and promising result from this study, Shafer said, is that pediatricians were receptive to changing their behavior regarding the sensitive topic of sexual health. Last year, the US Preventive Services Task Force urged doctors to screen all sexually active women 25 and younger; CDC has since issued similar guidelines. However, nationally only about 20 percent of women ages 15 to 25 who belong to managed care organizations are screened, according to the study. The reasons involve physicians' reluctance to ask adolescent patients about their sexual histories, and teenagers' reluctance to undergo pelvic exams, together with teens' fears that the results will not remain confidential.
HMOs currently pay for the test, and it is often administered free at public health departments. However, many providers may not view the screening as cost effective, especially if the patients are teenage girls who will be most likely to switch to another doctor later in life, said Dr. Kathleen Irwin, chief of CDC's Health Services Research Division of STD Prevention. Irwin said the study was a great example of what could be accomplished if chlamydia screenings became a regular part of preventative care, similar to annual Pap tests.