"Endometriosis is a very common gynaecological condition which can affect up to 15 percent of all women. Half of all women with endometriosis will be infertile. After fibroids, endometriosis is the most common gynaecological problem. The National Endometriosis Society estimates that between 1.5 and 2 million women in Britain have endometriosis. In the US that number is closer to 5 million.
"Endometriosis is more common in childless women over the age of 30. It is now believed that endometriosis is sensitive to oestrogen; therefore, women who have had more cycles, without a break for pregnancy, will have had more exposure to the female hormones. Today, with more and more women putting off having children until their later years, the incidence of endometriosis-linked infertility is increasing.

How does endometriosis cause infertility?
"Not only is endometriosis more common in older, childless women, but it can cause scarring that can block the fallopian tubes so severely that they are unable to pick up an egg at ovulation. Furthermore, the ovaries themselves may become scarred, which means that ovulation may occur but the egg becomes entrapped in scar tissue.

What is endometriosis?
"Endometriosis is a condition in which the lining of the womb (the endometrium) implants and grows outside the womb itself. These endometrial implants can grow in the pelvis, fallopian tubes, ovaries, bowel and bladder. More uncommonly, they can also crop up in the lung, heart, eye, armpit or knee.
"Wherever it grows, the womb lining responds to the natural hormone cycle and bleeds every time a period occurs. When women bleed normally throughout menstruation, blood leaves the body through the vagina. However, in the case of endometriosis, the blood has no outlet and becomes trapped in the tissue, causing pain, inflammation, cysts and scar tissue. You may find..."