During 24 years of follow-up, the researchers found, there were 1,975 premature deaths, including 894 from cancer and 172 from cardiovascular disease.
After factoring in age, weight, lifestyle, family medical history and other factors, the researchers found that women who reported always having irregular menstrual cycles experienced higher mortality rates than women who reported very regular cycles in the same age ranges.
Similarly, Science Daily wrote, “women who reported that their usual cycle length was 40 days or more at ages 18-22 years and 29-46 years were more likely to die prematurely than women who reported a usual cycle length of 26-31 days in the same age ranges.”
The researchers noted that because their study was observational, they couldn’t establish cause. However, because of the large number of participants and high follow-up over many years, the researchers emphasize “the need for primary care providers to include menstrual cycle characteristics throughout the reproductive life span as additional vital signs in assessing women’s general health status.”