Pelvic inflammatory disease: pill risk.

Physicians who prescribe oral contraceptives and women who take them may want to think twice before using them in hope of decreasing risk of pelvic inflamatory disease (PID), a general inflammation of the pelvic cavity that can lead to infertility. Although previous studies showed that oral contraceptives decrease risk of PID caused by gonorrhea, a study reported in the April 19 JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION suggests that the pill does not protect against, and may even enhance, PID caused by chlamydia.

Chlamydia, which has been called the veneral disease of the '80s, is a bacterial infection that afflicts between 3 million and 10 million women and men in the United States each year, more than are afflicted by syphilis, herpes or gonorrhea. Its insidious course leaves many women without symptoms, but it can eventually lead to infertility. In men it causes painful urination and a mucoid discharge, which are often misdiagnosed as symptoms of gonorrhea. One out of five sexually active men harbor Chlamydia trachomatis, the offending bacteria, and can easily transmit the disease to their sexual partners, according to the Centers for Disease Control (CDC) in Atlanta. The number of women who carry the bacteria is not known, according to CDC.

CDC and researchers at the University of California at San Francisco School of Medicine became interested in the relationship between the pill, chlamydia and PID when they noticed that medical journals and textbooks recommended oral contraceptives because they are thought to decrease risk of PID. Intrauterine devices are known to increase risk of PID (SN: 8/20/83, p. 127).

The researchers looked at published studies of the relationship between the pill and PID or chlamydia. They found that most studies of the first type involved hospitalized women with severe forms of PID and did not distinguish between gonococcal and chlamydial forms of the disease. This design selects for women with gonococcal PID, says UCSF's Eugene Washington, because women with gonococcal PID have more severe symptoms than those with chlamydial PID and are more likely to seek hospitalization. The researchers conclude that this type of study "only suggests that oral contraceptives may protect against clinically severe PID, where ... gonorrhea plays an important role," but does not consider chlamydial PID.

When they examined studies of the relationship between oral contraceptives and chlamydia, they found that 12 of 14 published studies reported a two- to threefold increase in chlamydia among oral contraceptive users. The researchers suggest that changes in the cervix, the "neck" of the uterus that connects it to the vagina, may account for the increased chlamydia. In some women the pill causes cervical ectropion, a coiling outward of the vaginal end of the cervix that exposes more surface area to chlamydial infection. This can allow more bacteria to travel through the uterus and into the fallopian tubes, which become inflamed and eventually scarred. If scar tissue blocks the fallopian tubes, it can cause infertility or ectopic pregnancy, in which a fertilized egg becomes implanted and begins dividing in the fallopian tubes.

Washington emphasizes that the recent research is not a push for women to give up the pill. "But women and clinicians should keep an eye out for chlamydia infection," he says. Hunter Handsfield, director of the Sexually Transmitted Disease Program at the Seattle-King County (Wash.) Health Department, which is developing chlamydia screening program, recommends that sexually active women be tested once a year for chlamydia. A simple monoclonal antibody test developed by several companies last year facilitates detection, he says, and is available at most hospital laboratories.