Science advances, 2024
Abstract
The ovarian cycle has a well-established circa-monthly rhythm, but the mechanisms involved in its regularity are unknown. Is the rhythmicity driven by an endogenous clock-like timer or by other internal or external processes? Here, using two large epidemiological datasets (26,912 cycles from 2303 European women and 4786 cycles from 721 North American women), analyzed with time series and circular statistics, we find evidence that the rhythmic characteristics of the menstrual cycle are more likely to be explained by an endogenous clock-like driving mechanism than by any other internal or external process. We also show that the menstrual cycle is weakly but significantly influenced by the 29.5-day lunar cycle and that the phase alignment between the two cycles differs between the European and the North American populations. Given the need to find efficient treatments of subfertility in women, our results should be confirmed in larger populations, and chronobiological approaches to optimize the ovulatory cycle should be evaluated.
Topics
menstrual cycle circadian rhythm, endogenous ovarian cycle timing, circa-monthly cycle mechanism, menstrual cycle regularity, lunar cycle menstrual synchronization, ovulatory cycle clock mechanism, cycle timing system women, menstrual cycle circamonthly, internal clock reproductive cycle, cycle charting biological basis, menstrual rhythm epidemiology, cyclic ovulation periodicity
PMID 38598621 38598621 DOI 10.1126/sciadv.adg9646 10.1126/sciadv.adg9646 Ecochard et al. 2024, Ecochard 2024
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