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Women's Health

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Pelvic Inflammatory Disease - Cause

Pelvic inflammatory disease (PID) is caused by bacteria entering the reproductive organs through the cervix. When the cervix is infected, bacteria from the vagina can more easily get into and infect the uterus and fallopian tubes.

Sexually transmitted infections

Pelvic inflammatory disease (PID) is usually caused by a sexually transmitted infection (STI) that infects the cervix camera.gif.

When the cervix, which connects the upper vagina to the uterus, is infected with an STI, other bacteria in the vagina can more easily get into and infect the uterus and fallopian tubes.

The most common STIs that cause PID are gonorrhea and chlamydia.

PID caused by chlamydia may have milder symptoms or no symptoms (compared with PID caused by gonorrhea), which can delay diagnosis. PID caused by chlamydia is most common among teenagers and young adult women.

Bacterial vaginosis

Bacterial vaginosis (BV) is a drop in the vagina's "good" organisms and an increase in its potentially "bad" organisms.

When this happens and the problem organisms spread into the uterus and fallopian tubes, PID can result. BV is not sexually transmitted.

PID and intrauterine devices (IUDs)

Inserting an IUD while there is infection in the vagina or the cervix can cause PID. This is especially likely if bacterial vaginosis or an STI is present at the time of insertion.

    WebMD Medical Reference from Healthwise

    Last Updated: March 12, 2014
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
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