Time to the final menstrual period

Abstract

Objective: To determine, for a woman aged >45 years, whether selected hormonal, health status, and demographic measures are related to the time to final menstrual period (FMP) from a point where 6 weeks separate the shortest and longest cycles experienced to date.

Design: Cohort study.

Setting: Volunteers in an academic research environment.

Patient(s): Ninety-nine menstruating women aged 46 years to 55 years on entry completed menstrual diaries, gave annual blood samples, and were interviewed annually. They were observed for a mean period of 1.5 years. Seventy-seven reached FMP during observation.

Intervention(s): None.

Main outcome measure(s): Time to reach FMP from the date of a marker event-the difference between the longest and shortest of recent cycles reaching 6 weeks.

Result(s): Women self-rating as in the transition have a greater "hazard" or probability of FMP at any time after the marker event. Allowing for this and other covariates, the hazard is estimated to increase by 30% (confidence interval [CI]: 10%, 60%) for each year of age and 50% (CI: 7%, 118%) for each unit increase in log FSH, measured at the time of the marker event.

Conclusion(s): For women aged >45 years, the time remaining in the menopausal transition from the day on which >or=6 weeks separate the longest and shortest recent cycles is related to self-rating of menopausal status and to serum FSH level. The median number of months remaining ranges from 11 for those with FSH of >20 IU/L and who see themselves as in transition to 21 months for those with lower FSH and who notice little evidence of being in transition.