The study, conducted by Harvard University and Tongji Medical College in China, interviewed more than 90,000 women about their menstrual history and followed them over a 12-year span.
It found that women who had irregular cycles when they were between the ages of 14 and 17 were 21 per cent more likely to die during the follow-up period after the study’s conclusion than women who had “very regular” menstrual cycles. More than half of the deaths were from cancer, and about ten per cent were from cardiovascular disease.
In women between 18 and 22 whose cycles were irregular, the likelihood of death was 34 per cent. “A similar association” existed in women whose periods were irregular between the ages of 28 and 48.
Death was also more likely in women whose cycles lasted more than 32 days, as compared to women whose cycles were the standard 26-31 days.
The existence of a link between cycle length or regularity with death does not mean that one causes the other, the study’s authors stress. The study has not yet been published, but findings were presented at the American Society for Reproductive Medicine, or ASRM’s, Scientific Congress and Expo in Philadelphia this week.
“Irregular cycling could be evidence of an underlying health condition,” the ASRM’s vice president Hugh Taylor said in a press release.
“But these clues are subtle and may not, in themselves, cause much worry. Patients who experience menstrual irregularity should be advised to maintain a healthy lifestyle and be alert to health changes.”
Periods that come at unpredictable times are most common in young girls and in women approaching menopause, because of changes in the body’s hormone levels, according to WebMD. But they occur at other times, too: “at least 30 per cent of women have irregular periods during their childbearing years,” obstetrician/gynecologist and university professor Dr. Amy Autry told Everyday Health.
Changes in period length can also be caused by changes in birth control methods, like starting on different pills or getting an IUD, as well as things like stress, lack of sleep, too much exercise, or uterine fibroids (noncancerous growths).
In some cases, though, irregular periods can be a sign of more serious issues, like hypothyroidism or polycystic ovary syndrome. Studies have also linked menstrual cycle health to metabolism, fertility, sleep and heart health.
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