Melatonin reproductive effects

Melatonin affects reproduction in seasonally breeding animals. In humans, findings of increased endogenous melatonin in hypogonadism and low concentrations in precocious puberty imply an interaction between melatonin and gonadotropins however, data on the effects of exogenous melatonin are limited (1). In a randomized study in 16 women, melatonin enhanced LH and FSH responses to submaximal GnRH stimuli in the follicular but not the luteal phase of the menstrual cycle (24). 

Because melatonin production goes down during puberty, some researchers suspect that the decreasing levels of this hormone are somehow linked to sexual maturation. Melatonin also influences the levels of certain reproductive hormones such as prolactin and luteinizing hormone. Due to these effects, many experts recommend that children, teenagers, pregnant women, and breastfeeding mothers do not take melatonin. 

Melatonin influences the level of other hormones in the body. It has been shown to have a particularly strong effect on prolactin and luteinizing hormone, both of which are major reproductive hormones. Some authorities caution that it may reduce the sexual drive in men. 

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