Research progress and future directions in circadian rhythms for uterine‑related diseases (Review)

Circadian rhythms are ~24 h endogenous rhythms driven by both central and peripheral clocks, with their core mechanism being a transcription‑translation feedback loop mediated by master clock genes. The present review outlines the organizational features and regulatory mechanisms of uterine circadian rhythms: Clock genes in the endometrium exhibit phasic rhythmic changes, which are lost after decidualization; rhythmic expression of clock genes in the myometrium influences uterine contractions and regulates the timing of labor. Estrogen and progesterone can modulate core clock genes and affect the decidualization process. As a key output hormone of the central clock, melatonin also modulates the uterine environment and influences delivery timing. Circadian rhythm disruption is associated with the development of diseases such as endometriosis, endometrial cancer and menstrual disorders. Finally, limitations of current research and future directions are discussed to inform rhythm assessment and intervention strategies.