What causes polycystic ovarian syndrome?
The cause of PCOS is not known exactly but probably results from a combination of several related factors.
Women with PCOS frequently have a mother or sister with PCOS. But there is not enough evidence yet to say there is a genetic link to this disorder.
There may be an imbalance between a hormone produced by the brain (pituitary) called luteinizing hormone (LH) and follicle-stimulating hormone (FSH), resulting in a lack of ovulation and an increased testosterone production, a male sex hormone.
Many women with PCOS have a weight problem. So researchers are looking at a relationship between PCOS and the body's ability to make insulin. Insulin is a hormone that regulates the change of sugar, starches and other food into energy for the body's use or for storage. Many women with PCOS have insulin resistance, in which the body cannot use insulin efficiently. Since some women with PCOS make too much insulin, this leads to high circulating blood levels of insulin, called hyperinsulinemia. It is believed that hyperinsulinemia is related to increased levels of male hormones and it is possible that the ovaries react by making too many male hormones, androgens. This can lead to acne, excessive hair growth, weight gain (obesity), and ovulation problems as well as type 2 diabetes. In turn, obesity can increase insulin levels, causing worsening of PCOS. If there is evidence of being overweight a blood test to assess whether there is a tendency to develop diabetes (Oral glucose tolerance test) is sometimes recommended.
Treatment of polycystic ovarian syndrome
Lifestyle change and change in diet are absolutely paramount. The long-term consequences of PCOS should also be highlighted. Prophylactic use of a drug call Metformin in women with impaired glucose tolerance to prevent progression of diabetes may be useful in selected cases but this has to be decided by the doctors on a case by case basis at present. The effectiveness of Metformin in relation to ovulation induction has been evaluated and the most recent studies concluded that clomiphene citrate (CC) should still be the first choice therapy for women with therapy naïve PCOS (no previous treatments). In women who do not respond to clomiphene, a combination therapy with Metformin may be considered.
Take home messages for polycystic ovarian syndrome
- The condition never presents itself in exactly the same way in every woman - symptoms are highly variable
- Not all women with PCOS are infertile
- Treatment of PCOS is highly individualised
- Lifestyle changes and exercise are extremely important to manage the condition
- Metformin is a drug which may have a role in treatment of PCOS and a six month trial is worthwhile especially in women with PCOS who are overweight
- For women requesting cycle control oral contraceptive pill with anti-androgen activity (Yasmin) may be useful
- Clomiphene is the initial treatment of choice in women who are trying to conceive
PCOS is a very common problem that has both short-term effects upon reproductive function and longer term effects upon the risk of diabetes and cardiovascular disease. Treatment of this condition should not only include drug therapy but also lifestyle changes.
Mr Joseph Aquilina, FRCOG, is a Consultant Obstetrician and Gynaecologist at St. Bartholomew’s and The Royal London Hospitals. He provides a specialist service in Gynaecological Ultrasound and is recognised as a Preceptor for training in gynaecological scanning by the Royal College of Obstetricians and Gynaecologists. He offers a comprehensive one-stop service in the management of PCOS, menstrual disorders and pelvic pain. He is available for consultations at the London Bridge Hospital on Tuesday afternoons/early evening.
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