Polycystic ovary syndrome and subfertility

 

A disorder of ovulation (eg release) is one of the most common causes of subfertility, affecting some 25-30% of couples. It has been estimated that three quarters of the women with this problem have polycystic ovary syndrome which makes it one of the most common causes of subfertility.

What is a Polycystic Ovary?
The term polycystic literally means "many cysts" but this description is misleading and, for many women, worrying because of the word "cyst". It conjures up the vision of diseased ovaries and, understandably, even raises the question of cancer. It is important to emphasize that all ovaries, if they are functioning formally, contain "cysts". These cysts are more correctly called "follicles" and are vital to the reproductive process because they contain the eggs. The only differences between "polycystic" and "normal" ovaries are that polycystic ovaries are usually somewhat larger than average and contain about twice as many, but normal, follicles - hence "polycystic". Polycystic ovaries are not, in themselves, abnormal. About 1 in 5 of the general female population have polycystic ovaries and only a small proportion of these women will have fertility problems. We do not yet fully understand what other factors must be present in a woman with polycystic ovaries for her to go to develop polycystic ovary syndrome and subfertility.


What is Polycystic Ovary Syndrome?
The typical features of polycystic ovary syndrome (PCOS) include a disturbance of the pattern of menstrual periods (sometimes no periods at all, but, more commonly, irregular and infrequent menstruation) together with some degree of unwanted body hair. However, it is important to point out that whilst growth of unwanted hair may be very troublesome for some women with polycystic ovaries, it is only moderate in most (and easily managed by simple cosmetic measures) and does not occur at all in a substantial number (4 out of 10) with the syndrome.

There is also an association between PCOS and body fat. About one third of women with this disorder are overweight and it appears that women with PCOS may have a slightly different metabolism from women without the syndrome which makes them more prone to gain weight. However, the important point is that weight reduction in overweight women with PCOS improves fertility.


How is the Diagnosis Made?
The diagnosis of PCOS is obviously suspected in a woman with infertility who is having irregular, infrequent or no periods, particularly if she also has unwanted body hair. It can be confirmed by performing an ultrasound scan of the ovaries. Blood tests are also taken for hormone measurements as most women with PCOS have evidence of a hormone imbalance which may be an important factor in causing the problem with ovulation.

Fortunately, most women who are subfertile because of PCOS are able to get pregnant as a result of treatment to stimulate ovulation. They key to treatment lies in increasing the levels of "follicle-stimulating hormone" (FSH) in the blood. The first line treatment is the use of clomiphene.


How can it be Treated?
(Clomid) or other similar "anti-estrogens". It works by stimulating the body's own supply of FSH from the pituitary gland. Clomiphene is given in tablet form and is usually prescribed for five days shortly after the start of period. This is successful in about three quarters of patients with PCOS.

Treatment is more complicated in the 25% of women who do not respond to clomiphene and should be given and supervised at a specialist infertility centre. In such cases it may be necessary to give FSH by injection, usually in Pergonal, (Humagon) or "pure" FSH (Metrodin). They are all equally effective but care must be taken to avoid overstimulating the ovary as this can lead to severe swelling of the ovaries ("hyperatimulation syndrome") and increases the risk of multiple pregnancy. For this reason some centers (including our own) have adopted a "low dose" scheme for the use of FSH and have been able to reduce the incidence of these worrying side effects.

Also available are surgical methods of treatment - ovarian wedge resection or (more recently) "drilling" of the surface of the ovary through laparoscope. However, many experts think that these treatments should be reserved for those women who do not respond to, or are thought unsuitable for, medical treatment. As mentioned earlier, a calorie-controlled diet is an important part of treatment in overweight women with PCOS. The response to clomiphene or to FSH is much better in women of normal weight compared with those who are overweight.