In most women who have it, chlamydia travels no further than the cervix (neck of the womb at the top if the vagina). But in about 1 in 10, it travels further upwards through the uterus (womb) into the Fallopian tubes. In the Fallopian tubes it can cause inflammation known as �pelvic inflammatory disease� or PID. Other types of bacteria may then move in making the inflammation worse. PID may be painful, but can occur without any pain at all. If the infection is treated at this stage, the tube may recover completely, or some scarring and other damage may remain.
The Fallopian tube is where the sperm meets the egg, and where fertilization occurs. So if a woman�s tubes have been damaged by PID in the past, the egg and sperm will not be able to travel along it easily, and she may not be able to conceive. If she does conceive, there is a possibility that the fertilized egg could get stuck in the tube, and the baby would start to develop in the tube instead of in the uterus. This is called �ectopic pregnancy�.
However, while it is true that chlamydia can cause infertility, this happens in only a small number of women who have it. The risk is not precisely known, but a Swedish study in the early 1990s suggests the following figures:
If 100 women get a chlamydia infection, 20 will develop PID.
Of these 20 who develop PID, 2 will have difficulty conceiving and 1 will have an ectopic pregnancy.
The more times a woman has PID, the greater the damage to the tubes and the greater the chance of later problems. So if those 20 women had another attack of PID, 4 would become infertile and 2 would have ectopic pregnancies.
If those same 20 women had three or more attacks of PID, 8 or 9 would become infertile and 4 would have ectopic pregnancies.
It is important that if you do have chlamydia that you (and your partner) are treated as soon as possible through a course of antibiotics.