Prompt and appropriate treatment can help prevent complications of PID. Without treatment, PID can cause permanent damage to the female reproductive organs. Infection-causing bacteria can silently invade the fallopian tubes, causing normal tissue to turn into scar tissue. This scar tissue blocks or interrupts the normal movement of eggs into the uterus. If your fallopian tubes are totally blocked by scar tissue, sperm cannot fertilize an egg and you become infertile. Infertility also can occur if the fallopian tubes are partially blocked or even slightly damaged. About one in five women with PID becomes infertile.
In addition, a partially blocked or slightly damaged fallopian tube may cause a fertilized egg to remain in the fallopian tube. If this fertilized egg begins to grow in the tube as if it were in the uterus, it is called an ectopic or tubal pregnancy. An ectopic pregnancy can rupture the fallopian tube, causing severe pain, internal bleeding, and even death.
Scarring in the fallopian tubes and other pelvic organs can also cause chronic pelvic pain (pain lasting for months or even years). You are more likely to suffer infertility (20 percent of women), ectopic pregnancy (9 percent), or chronic pelvic pain (18 percent) if you have repeated episodes of PID.