Why you shouldn't take melatonin during pregnancy, according to OB-GYNs
- Melatonin is a naturally occurring hormone that helps regulate sleep-wake cycles.
- However, pregnant people should not take melatonin supplements as they aren't regulated by the FDA.
- There are also no substantial human studies on how melatonin affects pregnancy.
Getting enough sleep is difficult whether you're pregnant, or not. In 2018, an estimated one-third of Americans were sleep-deprived.
However, pregnancy can come with additional problems that make it hard to get enough sleep. For example, back pain, esophageal reflux, and increased urination during your third trimester can make it hard to sleep a full 7 to 8 hours through the night.
Therefore, you may feel compelled to reach for something that might help you sleep better, like a melatonin supplement. But that's not a good idea.
What is melatonin?
Melatonin is a naturally occurring hormone produced by the pineal gland within your brain.
Sometimes referred to as the "sleep hormone," melatonin plays an instrumental role in keeping your sleep-wake cycles on track.
You can also purchase melatonin as a supplement. In fact, millions of Americans take melatonin supplements to help drift off at night. But whether melatonin supplements are actually effective is still up for debate.
Does melatonin work?
One meta-analysis published in 2013 in PLOS ONE, found that while melatonin's effect on sleep was modest, it led to improved sleep quality, increased time spent sleeping, and a decrease in how long it took people to fall asleep. The study described the effect of melatonin on sleep as "modest." And, as the National Sleep Foundation notes, many studies fail to show that melatonin is more helpful than a placebo.
"Data is not convincing that melatonin supplements are effective but doses available in the over-the-counter products appear to be safe," says Lynn L. Simpson, MD, FACOG, the chief of Obstetrics at Columbia University Medical Center.
Likewise, taking melatonin supplements while pregnant is not recommended due to a lack of research on its effects.
Why melatonin isn't recommended during pregnancy
"Most doctors do not recommend melatonin supplementation during pregnancy," says Simpson.
Lisa Valle, DO, an OB-GYN at Oasis WSFC, agrees, noting that melatonin affects many systems and no long-term data is available on its safety during pregnancy.
The few studies that do exist are either small or have only been done in animals. For example, a small 2018 study in the Journal of Pineal Research, included 20 pregnant women who had early-onset preeclampsia. The researchers reported that taking melatonin helped extend the duration of a woman's pregnancy compared to study controls. However, more research is needed in larger samples to determine if doctors should prescribe melatonin to reduce the risk of premature birth in women with preeclampsia.
Moreover, a 2013 study done on rats found that pregnant rats given melatonin gained less weight and gave birth to lighter babies. But it's unclear if this would lead to the same outcome in humans.
Since taking melatonin while pregnant hasn't been studied enough, Valle says it's hard to know what would happen if a pregnant person took too much melatonin. "Short-term side effects can include nausea, headache, and drowsiness and fatigue."
Also, supplements are regulated by the Food and Drug Administration as food, rather than drugs. That means the manufacturer can make claims without substantiation on the packaging. And, a 2017 study in the Journal of Clinical Sleep Medicine found that melatonin supplements' strength varied by as much as 478% more than what was listed on the packaging.
Instead of melatonin supplements, Simpson says, many doctors recommend non-pharmacological strategies to aid sleep, such as relaxation techniques, a warm bath before bed, and dietary modifications. When in doubt, reach out to your healthcare provider.
"Pregnant patients should consult their doctor prior to taking melatonin supplements," she says.
How much melatonin is recommended if you're not pregnant
If you're not pregnant and are interested in taking melatonin, start with a low dosage, says Valle. "The recommended dosage for a non-pregnant woman would be 0.2 to 5 milligrams each day to take an hour before bed."
But don't overdo it - it's easy to fall into the trap of thinking that more melatonin will result in better sleep. In fact, taking too much of this supplement can result in headaches, nausea, dizziness, or irritability, according to the National Sleep Foundation.
Insider's takeaway
Doctors don't recommend pregnant people take melatonin since supplements are not regulated by the FDA. Additionally, no long-term, human studies have been conducted on how melatonin could affect pregnancy. Therefore, if you are struggling to sleep while pregnant, try relaxation techniques or dietary modifications.