It’s that time of the month again—cramps, mood swings, and the usual discomfort. But when your periods turn unusually heavy, last too long, or show up unexpectedly, most of us blame it on hormones. However, a new study suggests something else might be the real reason: high insulin levels.
Published in the journal Menopause, the study found that women with elevated insulin levels are three times more likely to experience abnormal uterine bleeding—which includes spotting between periods, unusually heavy flow, or cycles that stretch on for too long.
While most treatments for irregular periods focus on hormones or surgical options, researchers believe this discovery could open the door to preventing period problems through better blood sugar control and lifestyle changes.
“Few studies focus on prevention strategies for abnormal bleeding. Most just treat the symptoms,” said Dr. Andrea Salcedo, an OB/GYN at Loma Linda University School of Medicine in California, who led the study.
Abnormal uterine bleeding affects nearly 30 per cent of women during their reproductive years, causing both physical discomfort and emotional distress. At the same time, insulin resistance—a condition where the body stops responding properly to insulin—is becoming more common due to poor diets, lack of exercise, and obesity.
We already know that insulin resistance can lead to type 2 diabetes, a condition that affects the heart, kidneys, and eyes. But could it also affect the uterus?
“Typically, we think of organs like the heart or kidneys being impacted by high insulin,” the researchers wrote. “But the uterus may also be at risk.”
To find out, the team studied 205 women aged 18 to 54 who visited a gynecology clinic between 2019 and 2023. Among them, 116 women had irregular bleeding, while 89 had normal cycles. Blood tests revealed that those with high insulin levels had a threefold higher risk of abnormal bleeding.
One possible reason? Chronic inflammation is caused by high insulin, which has already been linked to menstrual issues in previous studies.
“These early results show the need for more research,” said Dr. Stephanie Faubion, medical director of The Menopause Society. “But it’s a promising step toward understanding how weight, insulin, and metabolism affect menstrual health,” she further said.
So, the next time your period feels off, it might not just be your hormones—it could be your blood sugar trying to tell you something. Hence, it’s best to visit a gynaecologist in case you experience irregular periods or heavy bleeding.
