Review, 2007
Does the menstrual cycle change your body clock and sleep?
Yes. Body temperature, hormone rhythms like melatonin and cortisol, and sleep quality all shift across the cycle, with the most noticeable changes after ovulation and around menses, based on a review of past studies rather than new data.
What they did
The authors reviewed existing research on circadian rhythms (body temperature, hormone levels, sleep-wake patterns) in healthy women at different menstrual cycle phases, and in shiftworkers.
What they found
In the luteal (post-ovulation) phase, body temperature is higher but its daily rhythm is flatter; melatonin and cortisol rhythms may also be blunted. Sleep quality feels worst around menses, though overall sleep timing stays stable, apart from more spindle activity and slightly less REM sleep in the luteal phase. Female shiftworkers report more irregular, longer menstrual cycles than non-shiftworkers, and circadian disruption is linked to higher breast cancer risk.
What it means for you
The findings suggest disrupted body clocks could be connected to period-related mood changes and reproductive health, but this is a summary of other people's research, not a new experiment, so it cannot prove cause and effect.
About the study
- Original title
- Circadian rhythms, sleep, and the menstrual cycle
- Authors
- Baker FC, Driver HS
- Journal
- Sleep medicine
- Year
- 2007
- Study design
- Review
- What was tested
- None tested; this is a review.
- Read the paper
- doi.org/10.1016/j.sleep.2006.09.011
Topics
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