Experts think frequently getting frisky may fool the body into thinking there is a chance of pregnancy.
Middle-aged women who romp weekly are 28 per cent less likely to experience the change over the next decade.
And those who still have sex at least once a month have a 19 per cent reduced risk.
Megan Arnot, from University College London, said: “The findings 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 trade-off between investing energy into ovulation and elsewhere, such as keeping active by looking after grandchildren.”
Scientists say their findings back up the “grandmother hypothesis”, where older women contribute to the fitness of younger individuals by caring for grandchildren.
The average age for the menopause in the UK is 51, with around two million Brits affected at any one time.
It is triggered when the body stops making the hormone oestrogen and can cause a wide range of symptoms, including mood swings, poor sleep, joint pain and lack of concentration.
The study, in the journal Royal Society Open Science, followed nearly 3,000 women with an average starting age of 45.
Prof Ruth Mace added: “The menopause is 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.”