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Updated: Jul 16, 2026
06:53
Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
Published on: November 11, 2016
Circadian rhythms, sleep, and the menstrual cycle
Fiona C Baker1, Helen S Driver
1Human Sleep Research Program, SRI International, 333 Ravenswood Avenue, Menlo Park, CA 94025, USA. fiona.baker@sri.com
Sleep Medicine
|March 27, 2007
Summary
Women
Area of Science:
- Chronobiology and Reproductive Health
- Investigating the interplay between circadian rhythms and the menstrual cycle
Background:
- The menstrual cycle and circadian rhythms are interconnected, influencing each other's patterns.
- Understanding these interactions is crucial for women's health, particularly concerning mood and reproductive function.
Purpose of the Study:
- To review the existing literature on circadian rhythms (temperature, hormones, sleep) across the menstrual cycle.
- To discuss the impact of circadian disruption on menstrual cycle regularity and related health conditions.
- To explore the potential links between circadian disruption, menstrual disorders, and breast cancer risk.
Main Methods:
- Literature review synthesizing studies on circadian rhythms in women throughout the menstrual cycle.
- Analysis of research on shiftwork, mood disturbances, and their effects on menstrual cyclicity.
- Examination of evidence linking circadian disruption to breast cancer risk.
Main Results:
- Body temperature is higher, but its rhythm's amplitude is reduced in the luteal phase compared to the follicular phase.
- Melatonin and cortisol rhythm amplitudes may also be blunted during the luteal phase.
- Sleep quality is poorest around menses; sleep architecture shows minor changes in the luteal phase.
- Circadian rhythm disruption is linked to menstrual irregularities and potentially increased breast cancer risk.
Conclusions:
- Circadian rhythm disruption negatively impacts menstrual function and may increase breast cancer risk in women.
- Further research is needed to understand the biological mechanisms linking circadian disruption to menstrual disorders and cancer.
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