Melatonin is a hormone naturally produced in the body and is commonly associated with regulating the sleep-wake cycle or circadian rhythm. Its popularity as a supplement has grown, with many individuals taking melatonin to enhance their sleep. It is also believed to have a role in reproductive health. However, its safety during pregnancy is an ongoing debate. Both the ovaries and placenta produce considerable amounts of melatonin, which is utilized throughout pregnancy and childbirth. The levels of melatonin noticeably increase at 24 weeks into pregnancy and further surge after 32 weeks.

Melatonin collaborates with oxytocin, a hormone that triggers labor, contributing to the process of labor and delivery. The hormone's levels peak during the night, possibly explaining why most women enter labor in the evening and early morning hours. Melatonin is also present in the amniotic fluid, and the fetus relies on the mother's melatonin supply while in the womb and for the initial 9-12 weeks post-birth. Hence, melatonin supplements can impact both the mother and the newborn.

The safety of taking additional melatonin supplements during pregnancy remains disputed. Even though melatonin is naturally occurring, it doesn't necessarily mean it's entirely safe. Any melatonin supplementation should be disclosed to your healthcare provider to avoid potential complications. There is no proven safety of melatonin in pregnancy, and the absence of a standard dosage complicates self-medication. Melatonin is generally deemed safe for short-term use, but its long-term effects are yet to be thoroughly researched.

One animal study has revealed that excessive melatonin during pregnancy adversely affected the maternal weight, newborn birth weight, and infant mortality. Potential side effects encompass drowsiness, nausea, headaches, and dizziness.

Research into the impacts of melatonin on pregnancy and infants in humans is still in its infancy. Nonetheless, some animal studies have drawn positive associations between melatonin and pregnancy outcomes.

However, comprehensive human studies are required to ascertain if melatonin supplementation should be specifically used for these conditions.

Melatonin supplements are typically available as dry pills meant for oral consumption. The usual dose of melatonin ranges from 1-3 mg, which increases melatonin levels 20 times above the normal level. Your healthcare provider should be consulted for a recommended dosage.

If you opt to take melatonin supplements, consistency in timing is crucial since it can affect your sleep-wake cycle. Therefore, taking the supplement at the same time daily is generally a good practice.