Pelvic inflammatory disease (PID) is a general term that refers to infection and inflammation of the upper genital tract in women. It can affect the uterus (womb), fallopian tubes (tubes that carry eggs from the ovaries to the uterus), ovaries, and other organs related to reproduction. The scarring that results on these organs can lead to infertility, tubal (ectopic) pregnancy, chronic pelvic pain, abscesses (sores containing pus), and other serious problems. PID is the most common preventable cause of infertility in the United States.
Women at greater risk for PID include those at risk for sexually transmitted diseases (STDs) and those with a prior episode of PID. Sexually active women under age 25 are at risk as well because the cervix (opening to the uterus) of teens and young women has greater susceptibility to STDs. This may be because the cervix of teenage girls and young women is not fully matured, increasing their risk for STDs linked to PID.
Other potential risk factors include douching. Douching can change the vaginal flora and can force bacteria from the vagina into the upper reproductive organs. In some women, using an intrauterine device (IUD) to prevent pregnancy can also cause PID. Rarely, PID results from gynecological procedures or surgeries.
In the United States, it is estimated that more than 750.000 women suffer from an episode of acute PID each year, according to the Centers for Disease Control and Prevention (CDC). Up to 10 to 15 percent of women may become infertile as a result of PID.
Although scientists have learned much about the biology of the microbes (germs) that cause PID and the ways in which they damage the body, they still have much to learn. Scientists supported by NIAID are studying the effects of antibiotics, hormones, and substances that boost the immune system. These studies may lead to insights about how to prevent infertility and other complications of PID.
More NIAID Research on PID
Last Updated November 29, 2011
Last Reviewed April 13, 2009