| Updated at: 1729 PST, Monday, October 18, 2010|
LONDON A simple genetic test could in future help women predict their reproductive lifespan.
Scientists have identified four genes that affect menopausal age. In combination they have a larger impact, leading some women to reach "the change" unusually early.
Study leader Anna Murray, from the University of Exeter Peninsula Medical School, said: "It is estimated that a woman's ability to conceive decreases on average 10 years before she starts the menopause. Therefore, those who are destined to have an early menopause and delay childbearing until their 30s are more likely to have problems conceiving.
"These findings are the first stage in developing an easy and relatively inexpensive genetic test which could help the one in 20 UK women who may be affected by early menopause."
On average women hit the menopause around the age of 51, but some experience their last period in their 40s.
Women taking part in the research were participants in the Breakthrough Generations Study, an investigation into the causes of breast cancer.
A total of 2,000 women who had experienced early menopause were compared with a matched number who had not.
DNA tests identified the four genes that each raise the risk of an early menopause.
The findings were published in the journal Human Molecular Genetics.
Professor Anthony Swerdlow, from the Institute of Cancer Research, principal investigator of the Breakthrough Generations Study, said: "We have made a valuable step towards helping women across the country identify and predict whether they are at risk of early menopause.
"This may in turn allow them to make informed decisions about their future fertility."