Women who have frequent intercourse near menopause would reach it less quickly than those who are not as sexually active. On average, having sex at least once a week has reduced the chances of going through menopause by 28% compared to women who have sex less than once a month, researchers said in the report on Wednesday. "Royal Society Open Science" review.
According to the study, this could be explained by a response of the body to the pressures of evolution. "If a woman has little or infrequent intercourse around the age of 40, her body will not receive the physical signals of a possible pregnancy," write Megan Arnot and Ruth Mace, scientists at University College. London. "From a perspective of maximizing physical fitness", the woman's body could then invest more of her energy in taking care of her family rather than in ovulation.
Previous research, seeking to explain why married women reach menopause later than never married or divorced women, has already discussed the influence of male pheromones, natural chemicals from the animal kingdom that attract the opposite sex.
A study carried out over several decades
To find out if either of these theories hold water, Arnot and Mace looked at data on nearly 3,000 women in the United States recruited in 1996 and 1997 to participate in a health study spanning several decades. This project (SWAN) made it possible to follow the biological and psychological changes occurring at the same time as menopause. The average age of the participants was 46 years. None had entered menopause, but just under half were "peri-menopausal" with minor symptoms that were beginning to appear.
Over the next decade, 45% of women experienced natural menopause, at age 52 on average. The correlation between the frequency of intercourse and the onset of menopause has been undeniable, according to the researchers. Since all of the relationships reported were heterosexual, the study does not say whether homosexual activity would have a similar effect.
The age of natural menopause varies considerably in different cultures. Genetic factors account for only about half of these differences.