Definition of Pelvic inflammatory disease (PID):

Pelvic inflammatory disease is a general term for infection of the uterus lining, fallopian tubes, or ovaries.

See also: Endometritis

Causes, incidence, and risk factors:

Most cases of pelvic inflammatory disease are caused by the same bacteria that lead to sexually transmitted diseases (such as chlamydia, gonorrhea, mycoplasma, staph, and strep).

The most common cause of PID is through sexual contact. However, bacteria may also enter the body after gynecological procedures such as:

• Childbirth
• Endometrial biopsy
• Insertion of an intrauterine device (IUD)
• Miscarriage
• Therapeutic or elective abortion

In the United States, nearly 1 million women develop PID each year. About 1 in 8 sexually active adolescent girls will develop PID before age 20. Since PID is often undiagnosed, statistics are probably greatly underestimated.

Risk factors include:

• Insertion of an IUD
• Multiple sexual partners
• Past history of any sexually transmitted disease
• Past history of PID
• Sexual activity during adolescence

Birth control pills are thought in some cases to lead to cervical ectropion, a condition that allows easier access to tissue where bacteria may grow. However, birth control pills may protect against PID by stimulating the body to produce a thicker cervical mucus. This makes it harder for semen to carry bacteria to the uterus.