Hormone discovery could pave the way for new treatments

POLYCYSTIC Ovary Syndrome is the most common female hormonal disorder, affecting about one in ten women in the UK . The ovary can often become enlarged with small cysts or follicles, leaving many sufferers infertile. Yet, finding out what causes this has proved problematic. Now, a breakthrough from St George's , University of London could provide part of the answer.

Though symptoms vary, previous research has shown that women with the syndrome (known as PCOS) have slightly higher than average levels of testosterone. But in the past few months Dr Helen Mason and her team in reproductive endocrinology at St George's, University of London have discovered another diagnostic clue — that levels of AMH, the hormone that turns the foetus into a male in the first few weeks after conception, are 75 times too high in the ovaries of women with PCOS.

Significantly, their study also showed that these concentrations of AMH, or Anti-M?llerian Hormone, inhibited aromatase, anenzyme that has a critical role during growth and selection of the follicle which will release the egg.

The group now plans to go on to discover why the levels of AMH are too high. “Very little is known about why follicles don't grow in COS ,” says Dr Mason. “We hope hat this work will provide a new venue of research which may lead to a treatment.”

In many women with PCOS, the higher level of testosterone causes hirsutism (unwanted hair) and acne, which can have devastating effects on their selfesteem and confidence. But for others, the symptoms pose greater health risks. A low metabolic rate — a common symptom of PCOS — means about 50 per cent of women with the syndrome are obese. This can increase their chances of developing type 2 diabetes in later life sevenfold. For the overweight, weight-loss is the primary treatment, but dieting isn't easy. Their low metabolic rate makes it harder to burn calories. Dr Mason estimates that sufferers have to eat the equivalent of a whole day's calories less each week to achieve weight loss. “You're looking at a lifetime of changing your eating habits,” she says. “I couldn't do it!”

Dr Mason's team's study was a collaboration with the University of Malta . Samples were collected from patients having their ovaries surgically removed in the UK and Malta and the tissue analysed for AMH. “This tissue is very scarce,” says Dr Mason “so these experiments can take years to perform.” Their persistence has paid off, as the research won the team an Exceptional Research Award at last year's meeting of the American Endocrine Society.