Study shows increased risk of heart disease and diabetes in women with irregular periods

Experts say links between menstrual disorders and metabolic health often overlooked. The study confirms findings from earlier research that women with irregular periods in their reproductive years have a greater chance of developing heart disease and diabetes later in life.

Irregular periods may be predictive of future heart disease and type 2 diabetes, according to new research.

The Australian study, published in Clinical Endocrinology, found that women who reported irregular menses were 20 percent more likely to develop cardiovascular disease (CVD) and 17 percent more likely to develop type 2 diabetes compared with women with regular menstrual cycles.

These findings highlight the importance of screening for diabetes and heart disease as is currently recommended in the most common conditions associated with irregular menstrual cycles in women in their forties, including polycystic ovary syndrome (PCOS) and early menopause, the authors write.

This study confirms findings from earlier research — women with irregular periods in their reproductive years have a greater chance of developing heart disease and diabetes later in life, says Rachel Urrutia, MD, assistant professor of obstetrics and gynecology at the UNC School of Medicine in Chapel Hill, North Carolina, who was not involved in the research.

“Although this is not a new finding per se, it reinforces findings from other places like the Nurses’ Health study in the U.S.,” says Dr. Urrutia. Those findings, published in The Journal of Clinical Endocrinology & Metabolism, found a significantly increased risk of CVD in women who reported irregular periods compared with women with normal cycles.

Research assessed risk over a 20-year period

Investigators collected and analyzed data from the women born between 1946 and 1951 who were participants in the Australian Longitudinal Study on Women’s Health 20-year follow up period.

A total of 13,543 women completed data on menstrual regularity, with 12,135 women (89.6 percent) reporting regular cycles and 1,408 (10.4 percent) reporting irregular menstrual cycles.

After analyzing the data using Cox regression models, researchers found an increased risk for both CVD and type 2 diabetes, leading them to conclude that menstrual cycles “appear to be an early indicator for heart disease and diabetes.”

Using the Cox regression method, scientists can explore certain variables (such as irregular periods) over a period of time to estimate the risk of a certain event — in this case, heart disease or type 2 diabetes.

Do irregular periods cause the increased risk of CVD and diabetes?

The study is not designed to see if the irregular cycles themselves cause the increased risks, says Urrutia. “However, most experts think that underlying health problems that cause irregular periods also cause a higher chance of cardiovascular disease and other metabolic diseases,” she says.

Although this study doesn’t account for the specific diagnoses that may be causing the irregular periods, most irregular periods are likely caused by polycystic ovaries, says Urrutia. PCOS affects about 1 in 10 women of childbearing age, according to the Office on Women’s Health.

The condition is caused by an imbalance of reproductive hormones which then creates issues in the ovaries. In women with normally functioning ovaries, the ovaries make the egg that’s released each cycle during ovulation; in women with PCOS, the egg may not develop normally, or it may not be released as it should be.

PCOS is linked with other health issues including diabetes, high blood pressure, high LDL (bad) cholesterol and low HDL (good) cholesterol, sleep apnea, and depression and anxiety, per OASH.

Link between hormone therapy and reduced diabetes risk

One interesting finding from the study was that people with irregular cycles who used hormone replacement therapy had a lower risk of diabetes than those who had not, says Urrutia. “We need more research to understand if there are specific groups who can actually benefit from hormone replacement therapy because we know that certain groups, such as older women, can actually have a higher risk of cardiovascular disease,” she says.

There are a few limitations to the research, says Urrutia. “The users were asked about ‘irregular periods’ — yes or no. We know that people who answer ‘yes’ to this question may be referring to very different things. For example, heavy monthly periods may be called irregular and those with periods every 45 days may call this regular,” she says. The authors were also unable to account for specific diagnoses, like polycystic ovaries versus thyroid disease, she adds.

Expert advice for women with irregular menstrual cycles

There are existing recommendations for women who have polycystic ovaries or other conditions that lead to irregular menstrual cycles, says Urrutia.

  • Work with your primary care provider to map out and follow a plan to improve your long-term cardiovascular disease and diabetes risk through exercise, high quality diet, stress management, weight loss as applicable, and medications such as metformin and statins.
  • Be should be sure to get regular screening for cardiovascular disease and diabetes because women with irregular periods typically transition into menopause earlier.