Study, 2021
How much does the menstrual cycle affect mood and body signs compared to daily, weekly, and seasonal changes?
The menstrual cycle causes the biggest changes in mood and body measurements compared to daily, weekly, or seasonal changes. Mood, vital signs, and sexual behavior vary most; sleep and exercise stay fairly steady.
What they did
Researchers tracked 3.3 million women across 109 countries using a health app. They recorded 241 million observations of 15 mood, behavior, and body measurements, and compared daily, weekly, seasonal, and menstrual cycles.
What they found
The menstrual cycle had the largest effect on most measured mood and body signs. Mood, vital signs, and sexual behavior varied the most with the cycle. Sleep and exercise changed less. Effects were consistent across countries.
What it means for you
For most women, the menstrual cycle causes bigger changes than daily or seasonal patterns. This very large international study makes results reliable. The findings apply across many countries and cultures.
3.3 million
women tracked
241 million
observations recorded
15
dimensions of mood, behavior, and vital signs measured
About the study
- Original title
- Daily, weekly, seasonal and menstrual cycles in women's mood, behaviour and vital signs
- Authors
- Pierson E, Althoff T, Thomas D et al.
- Journal
- Nature human behaviour
- Year
- 2021
- Study design
- Study
- Participants
- 3
- What was tested
- None - observational tracking
- Read the paper
- doi.org/10.1038/s41562-020-01046-9
Topics
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