12 November 2018
The US Nurses’ Health Study is well placed to follow a large cohort of women over time and a recent publication from this study has linked menstrual cycle characteristics in adolescence and early adulthood with eventual early menopause . In over 108,000 premenopausal women studied from a baseline age of 25–42 years, from the years 1989 to 2011, 2.6% of participants (n = 2794) underwent an early menopause (< 45 years) during follow-up. The authors of the paper reported that menarche at age 10 years (compared with 12 years) was a risk factor for early menopause, with a hazard ratio (HR) of 1.19 (95% CI 1.02–1.39). Other factors that were linked with an early menopause included cycle length < 25 days in early adulthood (18–22 years), with a HR of 1.71 (95% CI 1.47–1.96). Those with irregular cycles had a reduced risk of early menopause, HR 0.51 (95% CI 0.43–0.60), and women with a cycle length in early adulthood of ≥ 40 days had a similar reduction in risk of undergoing early menopause, HR 0.44 (95% CI 0.34–0.58). Hence it appears that factors that are associated with a higher frequency of ovulation at least early in reproductive life (and potentially throughout reproductive life if the pattern continues long term) may in fact be linked to an early menopause, with the reverse being true for those undergoing less frequent ovulation.
In most cases of premature or early menopause, a causative factor will not be found, which can be perplexing for women searching for answers for themselves and possibly also for their female children, who may also be at risk of undergoing menopause at a similar or even younger age. Hence the importance of research that attempts to find patterns or links that may point to markers that may be used to identify women at risk of undergoing an early or premature menopause.
Endocrinologist, Women’s Health Research Program, Monash University, Australia
Whitcomb BW, Purdue-Smithe A, Hankinson SE, Manson JE, Rosner BA, Bertone-Johnson ER. Menstrual cycle characteristics in adolescence and early adulthood are associated with risk of early natural menopause. J Clin Endocrinol Metab 2018;103:3909-18