Key clinical point: Consider the menstrual cycle as a vital sign of women’s general health.

Major finding: Among women reporting very regular cycles and women reporting always irregular cycles, mortality rates per 1,000 person-years were 1.05 and 1.23 at ages 14-17 years, 1.00 and 1.37 at ages 18-22 years, and 1.00 and 1.68 at ages 29-46 years, respectively.

Study details: Prospective observational cohort study of 79,505 premenopausal women

Disclosures: This study was funded by the National Institutes of Health. The investigators had no relevant financial disclosures.