pelvic inflammatory disease (PID), infection of the female reproductive organs, usually resulting from infection with the bacteria that cause chlamydia or gonorrhea. The infection typically first affects the cervical area, then spreads to the uterus, fallopian tubes, ovaries, and abdomen. Symptoms may be absent but usually include pelvic pain and vaginal discharge. PID can cause abscesses and scarring in the fallopian tubes that can block fertilization or interrupt the egg's progress, resulting in ectopic (tubal) pregnancy and loss of the fetus. Over 1 million women are diagnosed with PID each year in the United States; 100,000 typically become infertile.

Acute inflammation of the pelvic cavity in women, caused by bacterial infection (usually gonorrhea or chlamydia) of the reproductive system. Usually a sexually transmitted disease, it occurs mainly in sexually active women under age 25, more often in those using intrauterine devices (IUDs). PID can resemble gonorrhea, with abdominal and lower pelvic pain, chills, nausea, fever, and thick, foul-smelling vaginal discharge. Fallopian tube scarring can cause infertility and ectopic pregnancy. Treatment requires antibiotics, bed rest, pain medication, and sexual abstinence until the infection disappears. Sexual partners must also be treated to prevent reinfection.

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