Cohort study, 2025
Are irregular menstrual cycles linked to lower thinking and memory skills in middle-aged women?
Yes. Women with irregular cycles at ages 29-46 and women with very short cycles (25 days or less) at ages 18-22 both had slightly lower memory scores later in life.
What they did
A study of 19,904 female nurses from the Nurses' Health Study II. Researchers collected information about menstrual cycle regularity and length at ages 14-17, 18-22, and 29-46 years. They tested cognitive function around age 62 using a computerized assessment measuring thinking speed and memory.
What they found
Women with irregular cycles at ages 29-46 scored 0.05 SD lower in learning and working memory than those with very regular cycles. Women with cycles of 25 days or less at ages 18-22 scored 0.05 SD lower in learning and working memory in later life compared to those with cycles of 26-31 days. Women whose cycles were regular when younger but became irregular later also had lower memory scores.
What it means for you
Irregular or very short menstrual cycles may be linked to slightly lower memory skills in midlife. However, the differences are small, and the study measured cycles and cognition at different times in women's lives, so it cannot prove that cycle problems cause memory decline.
19,904
women studied
62.0 ± 4.9
mean age at testing (years)
≤25 days
shortest cycle length studied
About the study
- Original title
- Menstrual cycle characteristics across the reproductive lifespan and cognitive function in midlife women
- Authors
- Soria-Contreras DC, Wang S, Mitsunami M et al.
- Journal
- American journal of obstetrics and gynecology
- Year
- 2025
- Study design
- Cohort study
- Participants
- 19,904
- What was tested
- Observational analysis of menstrual cycle history and cognitive function
- Open access
- Yes
- Read the paper
- doi.org/10.1016/j.ajog.2025.01.025
Topics
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