For decades, scientists have been aware of the important role melatonin plays in regulating our sleep and wake cycles. The hormone, discovered in 1958 by dermatologist Aaron B. Lerner, is responsible for helping us maintain our daily sleep schedules by interacting with receptors in the brain to make us feel drowsy at night. Recently, however, researchers have made some startling discoveries about a few of melatonin’s other functions, namely its effects on — you guessed it — fertility!
Produced in the pineal gland near the center of the brain, melatonin is responsible for regulating our internal clocks. It is commonly available as a dietary supplement, and many use it to treat everything from jet lag to shift-work disorder to insomnia.
Scientists, however, have detected melatonin receptors not only in the brain, but also in many other parts of the body, including in the liver, skin, prostate, gallbladder, intestines, kidneys and ovaries, leading to the conclusion that melatonin’s effects go well beyond the regulation of sleep.
While much of the research is still new and developing, various studies have already found a strong link between melatonin and fertility, particularly as it relates to the development of egg cells.
One of the most recent studies testing the relationship between melatonin and fertility found that the hormone increased both the egg-laying rate and the quality of eggs in hens that were past their peak egg-laying age. Other studies involving mice, pigs, sheep, cows and even humans have yielded similar results: Melatonin promotes the development of egg cells and early embryos in various animals.
The potential applications of these findings are monumental; poor egg quality is one of the leading causes of infertility among women, and any drug or supplement capable of supporting conception is a welcome aid to couples hoping to become pregnant. In fact, one study found that taking 3 mg of melatonin helped women undergoing treatments for in vitro fertilization (IVF) to dramatically increase the chances of their eggs becoming fertilized (50 percent fertilization rate compared to 23 percent for those not taking the supplement). The women who took melatonin were also 9 percent more likely to become pregnant through IVF than those who did not.
These results are encouraging, and they challenge researchers to further their understanding of melatonin’s effects on the human body. However, the sheer number of melatonin receptors in the body points to the fact that there is still a lot about the hormone we don’t know, raising concerns about its widespread availability in pharmacies and supermarkets across the country.
Classified by the FDA as a dietary supplement, the sale of melatonin is virtually unregulated. For more than twenty years it has been sold over the counter as a non habit-forming remedy for a wide array of sleep ailments, with dosages ranging from 1 mg to as high as 10 mg, despite researchers’ findings that the optimum dosage for productive sleep is actually closer to 0.3 mg.
As new studies emerge linking melatonin to various essential bodily functions, scientists have become more convinced that consumers should resist self-medicating. Not only does the body produce much smaller dosages of melatonin than are commonly available in stores, but it also does so gradually over an extended period of time. Misusing melatonin can negatively impact sleep cycles, and with everything researchers have yet to learn about how it affects our bodies, the potential for counterproductive complications cannot be ruled out.
Still, as researchers learn more about how melatonin affects the body, they are bound to find new and exciting uses for it. While its effects on fertility are only just being discovered, it has great potential, and its usage — in a regulated medical setting — will undoubtedly help improve many users’ lives.