Cardiologists at a major Chinese medical university have found that extreme menstrual cycle lengths are tied to a higher risk of cardiovascular disease, including heart attack and atrial fibrillation. These findings were reported in JAHA, the Journal of the American Heart Association.
The typical menstrual cycle lasts about 22 to 34 days on average, though many women experience variability month to month. Irregular cycles—where cycle length fluctuates significantly—affect roughly one in five women. Prior studies have shown that irregular cycles correlate with multiple cardiovascular risk factors.
In the current study, researchers analyzed data from about 58,000 women over a 12-year span. At baseline, participants averaged around 46 years of age and had no prior cardiovascular disease.
The analysis revealed that cycles shorter than 21 days or longer than 35 days were associated with a higher likelihood of cardiovascular disease, showing a 19 percent increased risk compared with women who had normal cycles.
Shorter cycles were linked to a 29 percent rise in cardiovascular events, including coronary heart disease, heart attack, atrial fibrillation, stroke, and heart failure. Conversely, longer cycles carried an 11 percent higher risk for these events.
However, the length of the menstrual cycle did not correspond to a greater risk of stroke or heart failure in this study.
The researchers concluded that irregular menstrual patterns may coincide with poorer cardiovascular outcomes. They emphasized the public health importance of monitoring menstrual cycle characteristics across a woman’s reproductive life to support prevention strategies for atrial fibrillation and heart attacks in women.