In Vitro Fertility Goddess

Cause of Endometriosis Discovered

Tuesday 5 August, 2008

Source: Human Reproduction

British scientists have discovered what they believe is the root cause of endometriosis.

A team from the University of Liverpool identified an enzyme called telomerase which could be responsible for the painful condition that leads to infertility and heavy periods for millions of women worldwide.

Telomerase is released by cells in the inner lining of the womb during the latter stages of the menstrual cycle in women who are affected by endometriosis. It's also found in some special cells such as sperm and egg cells.

Lead researcher Dr Dharani Hapangama detailed the findings by saying that "endometriosis occurs when cells of the inner lining of the womb are found growing outside of the uterus. At the time of a woman's menstruation cycle these cells, called endometrial cells, are shed and can be expelled into the abdominal cavity. If these cells continue to live and are implanted in the pelvis and abdomen it can cause severe pain and in serious cases can lead to infertility".

What Dr Hapangama found is that the region known as the telomere which is located at the end of all chromosomes that prevents the chromosomes from destroying themselves during cell division "is abnormally long in women with endometriosis. During menstruation telomeres normally shorten in length with each cycle of cell division until they reach a certain length at which they can no longer divide. An enzyme called telomerase can extend the length of the telomeres so that they can continue to divide and this can happen in some special cells such as sperm and egg cells, but not normally in cells that make up the organs of the body.

However, the research shows that cells in the lining of the womb are unique in that they can express this enzyme in the early stages of the menstrual cycle when cell division is important, but not during the latter stages when implantation of the fertilised embryo becomes a priority.

Dr Hapangama added that "women who have endometriosis express this enzyme in both the early and late stages of the menstrual cycle which means that the cells will continue to divide and lose their ‘focus' in supporting the establishment of a pregnancy. As a result the lining of the womb may be more hostile to an early pregnancy, and the cells that are shed at this late stage in the menstrual cycle may be more ‘aggressive' and more able to survive and implant outside the uterus, causing pain in the pelvic or abdomen area."

The research is expected to help scientists develop new techniques for diagnosing and treating the condition.

Endometriosis is diagnosed in most cases in women aged between 25 and 40.