Perimenopause cycle tracker.

Perimenopause Cycle Tracker: how it works

STRAW+10 marks the early menopausal transition by a persistent difference of 7 days or more in the length of consecutive cycles, and the late transition by 60 days or more without a period. This tracker compares your logged cycle lengths against those two bleeding criteria and shows your variability. For example, cycles of 28, 29, 36, 27, 41 and 30 days have four changes of 7 days or more, and the pattern recurs, so they match the early-transition bleeding pattern.

STRAW+10, the 2011 Stages of Reproductive Aging Workshop update (Harlow and colleagues, 2012), defines the early menopausal transition (Stage -2) as increased variability in cycle length, a persistent difference of 7 days or more in the length of consecutive cycles, where persistence means recurrence within 10 cycles of the first variable-length cycle. The late transition (Stage -1) is amenorrhea of 60 days or longer. The tool takes the difference between each pair of consecutive cycles, counts those of 7 days or more, flags the early pattern when a second such change occurs within 10 cycles after the first, and flags the late signal if any entered cycle is 60 days or longer or if it has been 60 or more days since your last period began.

The NHS says menopause and perimenopause usually affect women between 45 and 55 but can happen earlier, and that one of the first signs is usually a change to your periods. STRAW+10 is a staging system for research and clinical use; this page applies only its bleeding criteria, not the hormone or ovarian markers, so it cannot say what stage you are in. Hormonal contraception, pregnancy, breastfeeding, thyroid problems and other conditions also change cycles, and you should talk to your clinician about any change.

Worked example. Cycles 28, 29, 36, 27, 41 and 30 days. The changes between consecutive cycles are 1, 7, 9, 14 and 11 days. Four are 7 days or more, the first between cycles 2 and 3 and another within 10 cycles after it, so the early-transition bleeding pattern is flagged. The average is 31.8 days and the standard deviation is 5.49 days. Add a 64 day cycle at the end and the late signal (60 days or longer) is also flagged.