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Pelvic Inflammatory Disease

Understanding PID 

  • Cause
  • Symptoms
  • Diagnosis
  • Treatment
  • Prevention
  • Complications
  • 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 infections (STIs) 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 STIs. This may be because the cervix of teenage girls and young women is not fully matured, increasing their risk for STIs linked to PID.

    Other potential risk factors include douching, which women should avoid. 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 1 million women seek treatment for acute PID each year, according to the Centers for Disease Control and Prevention (CDC). A similar or greater number of women may have PID and not know it.

    Every year, more than 100,000 women become infertile and more than 150 women die from PID or its complications. PID is more common among teenage than adult women. It is also more common among African-American and Hispanic women.

    NIAID Research on 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 the National Institute of Allergy and Infectious Diseases (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

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    Volunteer for Clinical Studies
    Volunteer for NIAID-funded clinical studies related to pelvic inflammatory disease on ClinicalTrials.gov.

    See Also

  • Sexually Transmitted Infections News Releases
  • Sexually Transmitted Infections
  • Related Links

    View a list of links for more information about pelvic inflammatory disease.

    NIAID Publications order form Order Publications

    NIAID Publications order form



    Volunteer for Clinical Studies
    Volunteer for NIAID-funded clinical studies related to pelvic inflammatory disease on ClinicalTrials.gov.

    See Also

  • Sexually Transmitted Infections News Releases
  • Sexually Transmitted Infections
  • Related Links

    View a list of links for more information about pelvic inflammatory disease.

    NIAID Publications order form Order Publications

    NIAID Publications order form