COMMENT:WOMANHOOD IN FAST FORWARD

Normal menopause, even with its roller coaster of hot flushes and erratic periods, is a natural stage in a woman’s growth. But for the prematurely menopausal woman, there is a sense that, somehow your life has been jammed in fast forward.

No one is sure why some women experience the menopause at an earlier age. It can be genetic, or caused by metabolic disorders or viral infections. But surgery, radiotherapy or chemotherapy can also be the culprits.

The official line is that surgical removal of the ovaries and uterus can trigger menopause. What you’re less likely to be told is that any form of pelvic surgery risks disrupting the ovaries’ blood supply.

One such procedure is tubal sterilisation. Sterilisation is chosen by thousands of women each year as an ultimate method of birth control. Usually performed as a laparascopy, two small abdominal incisions are made, allowing a narrow instrument through to clip, cut, cauterise or constrict the fallopian tubes in order to block the passage of sperm to the egg.

Anyone considering sterilisation will be counselled by their GP, their Family Planning Clinic or their surgeon as to the implications of such a procedure. To paraphrase from the BPAS leaflet: Sterilisation should be regarded as permanent; there is a very slim chance of getting pregnant if the tube has not been completed sealed; there is a slightly higher risk of an ectopic (tubal) pregnancy; most women continue to have normal periods, although about one in 10 find their periods are a little heavier; sterilisation does not affect hormone production so there is no effect of early menopause.

The latter is a rather strong statement particularly since medical journals have been debating precisely this since the 70s. And despite regular new research, the jury is still out on whether tubal sterilisation can disrupt a woman’s ovarian functions enough to bring on perimenopause.

Early negative reports were inevitably dismissed as being poorly set up. However, in 1984, one study found that, while early studies of “post tubal ligation syndrome” had “serious methodological problems”, it still had to be admitted that “there was some data to support the concept that, in certain individuals, sterilisation may result in disruption of ovarian blood or nerve supply” (Fertil Steril, 1984; 135: 1368-81).

One hypothesis is that an oestrogen deficiency can occur if the ovarian artery is blocked during sterilisation (The Lancet, 1985; i: 847-849). The ovary’s production of these hormones depends on blood supply. The same author later showed that oestrogen excretion dropped further over a longer time frame following a tubal ligation.

In 1992, the Division of Reproductive Health in Atlanta published the result of a 10 year survey. It showed a marked difference between the menstrual cycles of women one and five years after they had undergone tubal sterilisation. The authors concluded that if tubal sterilisation affects menstrual function, such changes may take time to develop (Am J Epidemiol, 1992; 135: 1368-81).

Another study discovered a significant drop in progesterone levels with an significant increase in follicle stimulating (FSH) and luteinising (LH) hormone levels, in their study group of 43 women before and after tubal ligation (Adv Contracept, 1994; 10: 51-56). Two years later, a Finnish study came to a similar conclusion by studying progesterone levels in 55 women before and after tubal sterilisation (Obstet Gynecol, 1996; 88: 797-796).

The research continues and conflicts abound. Britain’s leading exponent of HRT, John Studd, is dismissive. His view is that most women who are sterilised are in their early 40s, so they are probably already entering perimenopause naturally. Charles Kings land, head of reproductive and endocrinological medicine at the Liverpool Women’s Hospital, however, regards ovarian failure as one of the most underdiagnosed conditions around. He agrees that pelvic surgery runs the risk of interrupting the blood supply. Even Dr Miriam Stoppard, in her book Menopause, claims that if tubal ligation does cause a loss of ovarian function, it is due to interference with ovarian blood supply.

Women who are contemplating sterilisation are entitled to know the real risks, however slim. Until researchers can ensure that tubal ligation methods will not affect the blood supply to the ovaries, then categorical statements like the one contained in the BPAS leaflet should be avoided.

Perhaps the most telling part of the leaflet is a disclaimer in a draft contract designed to be made between the patient and her doctor before sterilisation. It says: “I understand that no guarantees can be given that the operation will be successful or that it will be free from side effects..”

!AGeri Parlby

Geri Parlby, health editor of Positive News, underwent sudden perimenopause following sterilisation at 41.