Pelvic Inflammatory Disease (PID)

Pelvic inflammatory disease (PID) is an infection of the female reproductive system, including the cervix * , uterus * , ovaries * , and especially the fallopian tubes * . PID usually is the result of an untreated or poorly treated sexually transmitted bacterial infection. It can cause scarring, and reduce or eliminate a woman's ability to get pregnant.

Carrie and Reg's Story

Two years after Carrie and Reg got married, they decided to start a family. Carrie began looking at the ads for strollers and baby clothes. But after a year, she had not gotten pregnant. She was sure she did not have a medical problem. After another six months of trying, Carrie and Reg decided to see a doctor who specializes in fertility problems.

The doctor asked Carrie if she had ever had pelvic inflammatory disease (PID). She said no, and that she had not even heard of it. But in a series of tests, her body told a different story. Carrie's fallopian tubes (the place where the egg meets sperm in conception) had been scarred by PID.

Pelvic inflammatory disease (PID) risk factors

Pelvic inflammatory disease (PID) risk factors
Table by Corey Light. © 2016 Cengage Learning®.

After the doctor used laser surgery to remove the scar tissue, the blocked passages were opened, and Carrie finally got pregnant.

When healthy young women have difficulty getting pregnant, damage from PID is one of the many possible causes. In most cases, the women did not know they had the disease and never got treated. Quick treatment of PID can reduce the chances that it will cause infertility.

What Causes Pelvic Inflammatory Disease?

Most often, women get PID as a result of having a sexually transmitted bacterial * infection that was not treated, often because it was not noticed. The bacteria Chlamydia trachomatis and Neisseria gonorrhoeae are the most common bacteria involved in PID. The infections they cause are called a chlamydial (kla-MIH-dee-ul) infection and gonorrhea (gon-o-REE-a). PID can involve more than one type of bacterium. In many cases, doctors do not identify the specific bacterium involved.

Most often, bacteria enter the vagina * during sexual activity and then move up into the cervix, uterus, and other parts of the reproductive system where they rapidly reproduce. PID also can develop after a woman gives birth or has an abortion in unsanitary conditions. In rare cases, certain medical procedures done on reproductive organs, such as injecting dye for special x-rays, can lead to PID.

What Effect Does Pelvic Inflammatory Disease Have?

To understand the effect of PID, one has to understand the basic facts of conception. The ovary releases an egg each month into one of a woman's two fallopian tubes, where it meets with the sperm * . The newly formed embryo * travels through the tube to the uterus, which is an expandable organ. The embryo attaches to the wall of the uterus and grows into a fetus * .

* around the reproductive organs, a condition called pelvic peritonitis (per-i-to-NI-tis).

The body usually fights off the infection, but in the course of fighting the infection, tissues can be damaged and scar tissue may form. Scar tissue can block the delicate fallopian tubes. That means the egg and sperm may not be able to meet; or if they do, the fertilized embryo may not be able to reach the uterus.

Of women who have PID one time, about one in eight becomes infertile. Each repeat episode of PID doubles the chance of becoming infertile. The Centers for Disease Control and Prevention (CDC) estimates that 5 percent of U.S. women have reported being treated for PID in their lifetime. Women with PID are more likely to have tubal factor infertility (ranging from 8 percent after the first episode to as high as 40 percent after three episodes) and chronic pelvic pain (18 percent following one episode). Prompt treatment within three days of symptoms can help prevent infertility and other complications.

Women who have had PID are 50 percent more likely than other women to have an ectopic (ek-TAH-pik) pregnancy. Ectopic means that the embryo starts growing outside the uterus, usually in the fallopian tubes. Such a pregnancy cannot produce a baby, and if it is not ended it poses a very serious risk to the woman's life because the growing embryo will rupture the fallopian tubes and cause a life-threatening hemorrhage * .

Who Is at Risk of Acquiring Pelvic Inflammatory Disease?

About 1 million American women have a case of PID each year, of which about 150,000 are hospitalized due to complications of the infection. PID is rare among women who do not engage in sex. Sexually active teenagers are at the highest risk, followed by women in their early 20s. The risk increases if a woman has many sexual partners; has sex with a man who has many sexual partners; or has sexual intercourse very frequently even with a single partner. Frequent douching (inserting fluid into the vagina for cleansing) also increases the risk of PID. Women who use an intrauterine device (IUD) for birth control have a slightly increased risk of developing PID for a short time after the IUD has been inserted.

PID in the United States and the World

What Are the Symptoms of Pelvic Inflammatory Disease?

About 60 percent of all cases of PID have symptoms so mild that they go unnoticed. At the other extreme, symptoms can be quite severe. Noticeable symptoms are not specific to PID. They include the following: