A new study has uncovered the body wide, abrupt changes women experience as they begin menopause, but also found that certain therapy could help to reduce the impact.
Researchers in Israel found that women experience what they described as a “physiological cliff” before their final period, whereby many systems in the body undergo change in a sudden space of time, rather than gradually with age.
Many of these changes also point towards the direction of increased disease risk.
Menopause is when menstrual periods stop for 12 months or longer, and usually occurs in women around the age of 52 in the U.S., but age can vary from 45 to 55 years or older.
However, the experts also found that menopausal hormone therapy – previously called hormone replacement therapy – resulted in less drastic bodily changes for multiple systems in the body, though they cautioned that these findings were observational and required further investigation.
The study was published in the journal Nature Medicine on October 12.
Women Face ‘Physiological Cliff’ At Menopause
The researchers reviewed more than 300 million laboratory tests from over 1 million women across the U.S. and Israel between 1999 and 2024.
Uri Alon, the study author and a professor of molecular cell biology at the Weizmann Institute of Science in Rehovot, Israel, told Newsweek that they saw “gradual changes starting about a decade before menopause on average and accelerating in the years before the final menstrual period and then a jump at the final period.”
They found that sex hormones started to change in women’s bodies long before their final period. Anti-Müllerian hormone – the hormone that plays a role in fetal sex differentiation – and estradiol – a potent form of estrogen – had already begun to quickly decline around 15 and 12 years respectively beforehand.
Meanwhile, follicle-stimulating hormone – a hormone that regulated the growth and maturation of eggs – seemed to increase from around 14 years beforehand.
They also found that sudden changes happened across multiple biological systems in the female body before their final period. For example, in the U.S. dataset specifically and in 52 of 90 tests, the researchers identified notable, abrupt changes that affected sex hormones, bone health, liver and kidney function, blood chemistry, and blood fats.
“We can’t say for sure how rapid it is but it looks like it’s within the year of the final menstrual period,” he said.
Comparable changes were not observed in male individuals either. “When we apply the same approach to data from men they don’t have a jump,” he added. “They show changes of gradual aging over decades. Women also have these gradual changes plus the jump.”
The researchers said this indicated that menopause is more of an abrupt, multi-system physiological change that happens in the female body, rather than a part of normal ageing.
How Do These Changes Impact The Body?
Alon said that these sudden changes happen across body systems affected by estrogen.
For example, this includes “bone mineral density, which drops by about half a standard deviation on average in the population which can initiate bone loss or osteoporosis,” he said.
He added that by the age of 70, a quarter of women have osteoporosis. He said this is notable, as it means that what once might have been “a trivial fall” at age 50, “where you just brush it off and get up,” can then “cause a hip fracture at age 70, resulting in 20 percent mortality within a year and 50 percent disability, so we think this pandemic of bone fractures in older women is potentially preventable.”
He also said the liver is significantly affected by these changes, meaning women experience “a jump in liver damage tests and also risk of liver disease.”
Additionally, “there’s a jump in risk factors for heart disease, lipids, and triglycerides,” he said. “The silver lining is an improvement in iron and hemoglobin markers and a reduction of anemia and the reason is the stop of menstrual bleeding.”
Hormonal Therapy Reduced Impact
The researchers also found that women taking menopausal hormone therapy experienced reduced changes across several measures, particularly those related to bone, liver and kidney function.
The treatment works by replacing the hormones estrogen and progesterone in the body – both of which drop to low levels as a woman nears menopause – and therefore calms the sudden change in hormone levels in the body. It can reduce the symptoms of menopause, including hot flushes, night sweats, sleep problems, anxiety and low mood and others.
However, Alon said that this finding “is observational and based on a small minority of women that take [menopausal hormone therapy], and therefore should be taken with a grain of salt.”
He said that the treatment “erased most of the bone cliff and much of the heart marker cliff but because this is only observational it requires clinical trials to prove.”
Also, not all women are advised to have the therapy. Those who have a history of breast, ovarian or womb cancer; a history of blood clots; untreated high blood pressure; a liver disease; or those who are pregnant are generally not advised to take it.
What The Findings Mean For Women
Alon said that he hopes the findings “don’t cause stress or fear of menopause,” as he said they instead “emphasize the need to take care of exercise and nutrition and other healthy habits before the final menstrual period.”
“They also support consulting a physician especially if you have risk factors for bone, heart or liver [disease],” he added.
He also said that menopausal hormone therapy “is now given to prevent symptoms but future clinical trials may support whether [menopausal hormone therapy] before menopause can also be given for prevention [of disease].”
Reference
Pridham, G., Hayut, Y., Lavi-Shoseyov, N. et al. (2026) Population-scale reconstruction of menopause dynamics reveals a physiological cliff at the final menstrual period. Nature Medicine. https://doi.org/10.1038/s41591-026-04614-0
Contact Newsweek editors on this story: Marc Vargas and Paul Donnelley.