Menopause age linked to when mom went through it - study

NEW YORK (Reuters Life!) - The age at which women go through menopause depends a lot on when their relatives did, with women whose mothers and sisters went through it early likely to do the same, a study said.

Mother and daughter Lesley and Georgia MacDougall play in the sea near Brighton Pier in Brighton, southern England April 6, 2011. REUTERS/Luke MacGregor/Files

But the age of menopause is not entirely inherited, with a significant impact from so-called environmental factors, added study author Danielle Morris at the Institute of Cancer Research in the United Kingdom.

“Genes have an important effect on age at menopause, but lifestyle also matters, and so women can affect their age at menopause by their behaviors,” she added.

For instance, women who smoke tend to undergo menopause roughly 1-2 years earlier than former or non-smokers, while women who have never given birth also experience menopause earlier.

Age at menopause is an essential aspect of fertility, Morris and her team wrote in the journal Menopause, since a woman’s ability to conceive ends roughly 10 years before she experiences menopause.

Previous research has also found that women who experience menopause relatively late in life have a higher risk of breast and endometrial cancers, but a lower risk of cardiovascular disease.

According to the National Institute on Aging, the average age at which a woman reaches menopause, or has her last period, is 51.

Morris and her team compared women who were more or less related, reasoning that different relatives will share different amounts of genes and their environment.

The sample came from a large study designed to investigate the causes of breast cancer among women living in the United Kingdom. Among those participants, the team selected 2,060 women between the ages of 31 and 90 who had a first-degree relative who was also taking part in the study.

Both early and late menopause appeared to run in families, the researchers found -- but so did usual-age menopause.

Specifically, women whose sisters and mothers underwent menopause during a typical age were between 2 and 7 times more likely to do the same.

“For example, if identical twins have more similar menopausal ages than non-identical twins, then this suggests that genes are important because identical twins have more genes in common,” Morris wrote in an email to Reuters Health.

"Similarly, if sisters have more similar menopausal ages than mothers and daughters, then this (suggests) that environment is important, because sisters have the same among of genes in common as mothers and daughters do, but sisters tend to have more similar lifestyles than mothers and daughters."

Reporting by Alison McCook at Reuters Health; editing by Elaine Lies