Exploring melatonin’s multifaceted role in female reproductive health: From follicular development to lactation and its therapeutic potential in obstetric syndromes

The effects of melatonin on female reproduction encompass a range of processes, starting with the protection of oocyte quality and extending to the influence on embryo implantation, fetal development, and finally, parturition. Specifically, melatonin exhibits the ability to mitigate oxidative damage during both in vivo and in vitro follicular development. Additionally, it enhances uterine receptivity, facilitating successful follicular implantation. Moreover, melatonin holds promising potential in alleviating various reproductive diseases. It is worth noting that the absence of melatonin during pregnancy can significantly contribute to premature delivery as well as mental and metabolic disorders in offspring. [Display omitted] •Effects of melatonin on female reproduction beginning with protection of oocyte qualit up to parturition.•Melatonin has potential as a treatment for preeclampsia, endometriosis, polycystic ovary syndrome.•The benefits of melatonin on female reproduction are related to its antioxidant, anti-inflammatory, and reproductive hormone regulatory properties.•Melatonin on mammary gland development and milk production are less positive.•The use of melatonin appears to be safe, and so far, there is no tangible evidence of toxic effects. Melatonin is mainly secreted by the pineal gland during darkness and regulates biological rhythms through its receptors in the suprachiasmatic nucleus of the hypothalamus. In addition, it also plays a role in the reproductive system by affecting the function of the hypothalamic-pituitary-gonadal axis, and by acting as a free radical scavenger thus contributing to the maintenance of the optimal physiological state of the gonads. Besides, melatonin can freely cross the placenta to influence fetal development. However, there is still a lack of overall understanding of the role of melatonin in the reproductive cycle of female mammals. Here we focus the role of melatonin in female reproduction from follicular development to delivery as well as the relationship between melatonin and lactation. We further summarize the potential role of melatonin in the treatment of preeclampsia, polycystic ovary syndrome, endometriosis, and ovarian aging. Understanding the physiological role of melatonin in female reproductive processes will contribute to the advancement of human fertility and reproductive medicine research.