Untreated PID can interfere with a woman's ability to become pregnant.
If an infection in a woman's vagina or cervix spreads upward into her uterus and fallopian tubes, it could develop into pelvic inflammatory disease. If PID isn't treated promptly, it can damage and possibly block the fallopian tubes. This can interfere with the ability of an embryo to enter the uterus and, in severe cases, it might make a woman unable to become pregnant.
About 750,000 cases of PID are diagnosed annually in the U.S., most as a complication of sexually transmitted diseases such as chlamydia and gonorrhea, although common infections of the vagina can also develop into PID. In this disorder, the infection moves up from the vagina or cervix into the uterus, where it can involve the uterine lining, or endometrium. If it is untreated, the infection could progress into the fallopian tubes, which attach to and are continuous with the uterus. Symptoms of PID vary in severity, but can include lower abdominal pain, vaginal discharge, fever, irregular periods or pain during intercourse. Occasionally, it can cause lower back pain, pain urinating, vomiting or diarrhea, or a general sense of fatigue. If PID isn't treated promptly, it can cause complications that could interfere with a woman's fertility.
The fallopian tube is a delicate structure with an outer diameter of 0.2 to 0.6 inch and a narrow central channel. When a woman ovulates, the egg passes from the ovary into the open end of the fallopian tube, moves through its channel and enters the uterus, the site of embryo implantation. When PID involves the fallopian tube, the infection can cause scar tissue to build up in its wall, which can eventually block the channel. If only one tube is blocked, it's possible that a woman can still become pregnant when an egg enters the undamaged tube. If PID is not diagnosed and treated quickly, both tubes could be damaged by the infection and blocked by scar tissue. If this happens, a woman may become permanently infertile and unable to become pregnant.
A doctor who suspects PID can culture vaginal fluids and confirm the diagnosis with an ultrasound exam, which uses sound waves to provide black and white images of the pelvic organs. Sometimes, a doctor may also biopsy the uterine lining or examine the pelvic organs through a small abdominal incision. PID is treated with one or more antibiotics after the nature of the infection is identified. Antibiotic therapy is successful in curing the infection in up to 97 percent of cases of mild to moderate PID. Information about the effects on fertility after a severe case of PID that damages the fallopian tubes varies widely -- the outcome depends on the type of infection and the degree of scar tissue formation. However, a review of PID published in 2010 in the Journal of Infectious Diseases reports that up to 18 percent of women with PID that involves their fallopian tubes can become permanently infertile. In these cases, assistive reproductive approaches such as in vitro fertilization followed by embryo implantation may help a woman with PID-caused infertility have a child.
In some cases, symptoms of PID are deceptively minor or completely absent, a situation referred to as subclinical or silent PID. In a woman with silent PID, an infection moves into the uterus or fallopian tubes and may be present for some time before treatment is begun, potentially raising her risk of becoming infertile. This possibility was highlighted in a study published in September 2002 in Obstetrics and Gynecology, in which researchers found that between 15 and 27 percent of women with either a common vaginal infection or a sexually transmitted disease such as chlamydia or gonorrhea also had undiagnosed PID. If you have had an STD or have questions about PID and its potential impact on your fertility, discuss these in detail with your family doctor or a gynecologic specialist.