Scots experts decode biological clock and predict menopause

Published on Sunday 7 August 2011 13:07

SCOTTISH academics have found a new method that may help women to beat the biological clock by predicting how long they have left to have a baby.

A team of researchers from St Andrews, Glasgow and Edinburgh has found how levels of a hormone, which can reveal how many eggs a woman has remaining, change throughout her reproductive life.

The discovery will allow women to compare their own hormone levels with the average for their age to see whether they should be concerned about their future fertility. Tests will indicate whether they are likely to have an early or later menopause, meaning they know whether they have to try for a baby sooner rather than later.

The process will also help young women who have had treatment for diseases such as cancer, which may have affected their fertility, to find out whether their hormone levels have been affected.

Gauging female fertility has become more important, as more women are choosing to have children later, even though their reproductive lifespan is limited.

Figures show that the average age of mothers in Scotland has increased from 27.4 in 1991 to 29.6 in 2010. The number of women giving birth aged between 35 and 39 has risen from 6,577 in 1998 to 9,448 in 2009, while those over 40 rose from 981 to 2,006 in the same period.

But this trend has raised concerns that some will struggle to conceive if they delay motherhood for too long, leading to a search for ways of predicting when women should attempt to conceive.

For the latest research, the Scottish academics gathered together all previous data plus their own new findings on the Anti-Mllerian Hormone (AMH), which is produced by growing, egg-producing ovarian follicles.

They set out to map how levels of AMH vary at different points in the lives of healthy women by studying data from 3,200 women. They were able to deduce how a woman's AMH level compares with the average for her age as a result.

Findings could indicate whether they are likely to have an earlier menopause and should not delay trying to conceive, or whether their fertile life will end later.

The study found that AMH levels peaked at the age of 24 but had almost halved by the time women were in their mid-30s and were almost nonexistent by their late 40s.

Professor Scott Nelson, from the University of Glasgow, said a major use of the new findings could be in helping young cancer patients wondering how their treatment may have affected their chances of having a baby.

"We can now see 18-year-old girls, know what their AMH is and put that into context," he said.