More sex makes early menopause less likely
Women who have sex more often are less likely to have an early menopause, according to research that raises the intriguing possibility that lifestyle factors could play a more significant role than previously thought in determining when the menopause occurs.
The study, based on data collected from nearly 3,000 women who were followed for 10 years, found that those who reported engaging in sexual activity every week were 28% less likely to have experienced menopause at any given age than women who engaged in
sexual activity less than every month. Megan Arnot, a PhD student at UCL and the study’s first author, said the findings suggested that if a woman was not having sex – and there is no chance of pregnancy – the body might “choose” not to invest in ovulation.
“There may be a biological energetic trade-off between investing energy into ovulation and investing elsewhere, such as keeping active by looking after grandchildren,” she said.
The findings are based on data collected from 2,936 women recruited into a US menopause study called the SWAN cohort in the 1990s. The women
were aged 45 years on average at the start of the study and were mostly married or in a relationship.
The women were asked questions such as whether they had engaged in sex with their partner in the past six months, the frequency of sex, including whether they engaged in sexual intercourse, oral sex, sexual touching or caressing in the last six months and whether they had engaged in self-stimulation in the past six months.
The most frequent pattern of sexual activity was weekly (64%). None of the women had yet entered menopause, but 46% were
starting to experience symptoms of early menopause, such as changes in their period cycle and hot flushes. By the 10-year follow-up survey, 45% of the women had experienced a natural menopause at an average age of 52.
The study found women of any age who had sex weekly were 28% less likely to experience the menopause at any given age compared with those who had sex less than monthly. Those who had sex monthly were 19% less likely to experience menopause than those who had sex less often.
The researchers have yet to determine the biological mechanism that would result in sexual activity actively influencing when a woman’s reproductive cycle comes to an end.
The menopause is thought to occur when the number of maturing egg follicles in the ovaries drops beneath a critical threshold. One possibility is that sexual activity stimulates release of oestrogen, which plays a role in the complex cascade of chemical signals that result in an egg being released.
The study did not test this directly. A challenge, Arnot said, was that “the whole hormonal mechanisms surrounding the menopause is really poorly understood”, meaning the work does not slot neatly into a wellestablished framework.
Another possibility is that how often a woman has sex and her age at menopause are both determined by some other hormonal or biological factor not measured in the study, so the link would not be causal.
The study did not find later menopause linked to living with a male partner, suggesting exposure to male pheromones was not the reason.
Prof Ruth Mace, an evolutionary anthropologist at UCL and the paper’s senior author, said: “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.”