Having irregular or extra-long menstrual cycles could be a signal of early death, according to a study. Researchers have uncovered the link after studying the menstrual cycle of more than 90,000 women over two decades. Women whose periods fluctuated were up to a third more likely to die of any cause over the course of the study.
Doctors believe it could be because women with irregular periods have underlying health conditions that have not been spotted. Polycystic ovary syndrome (PCOS), which can cause irregular periods, is believed to be caused by insulin resistance – a risk factor for type 2 diabetes and heart disease.
The findings, presented at the American Society for Reproductive Medicine’s 75th Scientific Congress and Expo in Philadelphia, only found a correlation. Irregular periods are defined as periods that come early, or late, without a regular pattern.
The average menstrual cycle lasts 28 days. Women bleed for five days on average – but it is normal for it to be a bit shorter or longer than this, the NHS says. Researchers analyzed data on 93,775 women – who came from a variety of ages – between 1991 and 2013.
Participants had described the history of their menstrual cycles, reporting the usual length and regularity. They did this at ages 14 to 17, 18-22, and 28-48. The women had no history of cancer, diabetes, or cardiovascular disease at enrollment.
Researchers accounted for relevant mortality risks, including BMI, race or ethnicity, physical activity, and lifestyle factors. During an average of 18-year follow up, 1,679 deaths were recorded including 828 from cancer and 166 from cardiovascular disease.