Having sex on a regular basis may lower the risk of going through an early menopause, according to scientists.
A team from University College London (UCL) found that women who engaged in sexual activity – including intercourse, oral sex, touching or self-stimulation – on a weekly basis were 28 per cent less likely to have experienced the menopause.
Those who had sex every month were 19 per cent less likely to experience early menopause than those who had sex less frequently.
The team, who looked at the sexual activity of 2,936 women over two years, believe that the reason for this is because a lack of sexual activity signals to the body to “invest resources elsewhere”.
They say this is because ovulation is a “costly process” and if the body can better invest energy elsewhere, rather than getting pregnant, it will.
Megan Arnot, first author on the study, says: “The findings of our study suggest that if a woman is not having sex, and there is no chance of pregnancy, then the body ‘chooses’ not to invest in ovulation, as it would be pointless.
“There may be a biological energetic trade-off between investing energy into ovulation and investing elsewhere, such as keeping active by looking after grandchildren.”
The findings support the "grandmother hypothesis" which allows mothers to have more children as they are not in reproductive conflict with the generation of women above them.
Scientists believe women evolved to work in this way so populations would be invested in ensuring the survival of their grandchildren.
The study, which was published in Royal Society Open Science, looked at data from the US-based study of women’s health between 1996 and 1997.
None of the women had yet entered menopause at the start of the study and the average age at first interview was 45.
However, 46 per cent were starting to experience menopause transition when the study began, with symptoms such as changes in their period cycle and hot flashes.
The other 54 per cent were in the pre-menopausal stage, having regular cycles and showing no symptoms of menopause or menopause transition.
At the start of the study the women were asked to explain how often they had sex and whether they had taken part in oral sex, touching or masturbation in the last six months.
Professor Ruth Mace, one of the study authors, added: “The menopause is, of course, an inevitability for women, and there is no behavioural intervention that will prevent reproductive cessation.
“Nonetheless, these results are an initial indication that menopause timing may be adaptive in response to the likelihood of becoming pregnant.”