Women who go through menopause (end of a reproductive cycle) before the age of 40 are significantly more likely to develop serious cardiovascular conditions such as heart attacks and strokes, according to a new study published in The Lancet Obstetrics, Gynaecology & Women’s Health.

Using data from more than 111,600 women across 26 countries, researchers found that women with early menopause — defined as menopause between the ages of 40 and 44 — face a 30–40 per cent higher risk of cardiovascular disease compared to women who reach menopause at around age 45.

The findings from India were particularly striking. Of the 7,872 Indian women included in the study, 1,445 (18.4 per cent) had experienced premature menopause. The average age of menopause was 44.6 years, while 1,991 women (25.3 per cent) had experienced early menopause. Overall, 3,436 women (43.6 per cent) had experienced either premature or early menopause.

The study also found that women in low- and middle-income countries (LMICs), particularly in South Asia, tend to experience menopause earlier than women in wealthier countries.

Dr K. Srinath Reddy, Chancellor of the PHFI Institute of Public Health Sciences, who was not associated with the study, said that women are protected against heart and blood vessel disease before menopause because of the effects of female sex hormones on blood lipids, body fat distribution, inflammatory markers and vascular reactivity. “After menopause, this protection wears off and the risk of heart attack increases to levels seen in men,” Dr Reddy told The Indian Express.

The findings are based on the Prospective Urban Rural Epidemiologic (PURE) study, a multinational prospective cohort study that assessed 125,073 women aged 35–70 years from 28 countries for an association between age at menopause and cardiovascular events, including myocardial infarction, stroke and heart failure.

Researchers collected medical histories on diabetes and hypertension, while cardiovascular risk factors were assessed using the INTERHEART score, which includes smoking, lipid levels, hypertension, diabetes, obesity, diet, physical activity, alcohol consumption and psychosocial factors. The INTERHEART score comprises easily measurable and modifiable risk factors that account for more than 90 per cent of the risk of heart attack globally across regions and ethnic groups.

Among the 60,669 women who had reached menopause, 5,750 (9.5 per cent) had experienced premature menopause and 9,262 (15.3 per cent) had experienced early menopause. The remaining 45,657 women (75.3 per cent) had menopause at the usual age.

The average age of menopause across all countries was 47.4 years. However, it was considerably lower among South Asian women, at 44.7 years, and among women in low-income countries, at 44.8 years. In contrast, the average age was 47.8 years among European women and 48 years in high-income countries.

“This early menopause could increase their chances of developing serious cardiovascular disease later in life, including heart attacks and strokes,” said Dr Simone Marschner of the Westmead Applied Research Centre at the University of Sydney, Australia, and lead author of the study.

According to Dr Reddy, premature menopause can result from a range of factors, many of which are increasingly prevalent in low- and middle-income countries. Stress, tobacco use—particularly smoking—unhealthy diets high in refined carbohydrates and low in legumes and fruits, inadequate sleep, and both very low and excessively high levels of physical activity can all increase the likelihood of early menopause.

He added that environmental pollutants that act as endocrine disruptors, as well as heat exposure linked to global warming, may accelerate ovarian ageing and increase the risk of menopause occurring earlier. Diabetes is associated with a higher likelihood of premature menopause.

“Even second-hand smoke from male smokers results in passive smoking that can lead to early menopause,” Dr Reddy said. “The neuro-endocrine axis and gut-brain axis, which are sensitive to dietary and environmental exposures, play a role in altering the calendar of menopause.”

He noted that many of these adverse exposures are becoming more common in countries such as India, even as cardiometabolic diseases continue to rise. At the same time, gender differences in the risk of coronary heart disease are narrowing.

“Many of these exposures are modifiable through health-protective personal behaviours that are encouraged and enabled by supportive public policies. If women do not age prematurely under the assault of socio-environmental stresses, their hearts will be protected against heart attacks. This calls for a broader societal commitment to women’s health,” Dr Reddy said.

Arundhati Muralidharan, public health professional and co-founder of Menstrual Health Action for Impact, who was not involved in the study, said some research suggests that factors such as high rates of anaemia, early marriage, repeated pregnancies and nutritional status may influence menopause timing in India, although evidence remains limited.

“We need more clinical research to understand what is driving these differences and whether menopause patterns vary across income groups and regions within India,” she said.

Muralidharan pointed out that India already has strong public health programmes focused on non-communicable diseases such as diabetes, hypertension and cancer. However, there is very little information on whether healthcare providers routinely consider women’s age and menopause history while assessing these conditions.

“This presents an opportunity. Menopause screening and awareness could be integrated into existing programmes for diabetes, cardiovascular disease and hypertension, helping identify women who may be at higher risk during the menopausal transition. The goal is not only to manage menopause symptoms but also to support healthier ageing,” she said.