Getting the sleep you need while expecting can be tough! In fact, research suggests that up to 78% of pregnant folks experience sleep disorders. The uptick of both estrogen and progesterone levels, the increased need to pee, and your ever-growing bump can easily throw sleep off course. Plus, even moderate weight gain during pregnancy can make your airways swell, leading to sleep-disrupting snoring or obstructive sleep apnea, notes the American College of Gynecologists and Obstetricians. It’s no wonder so many parents-to-be are asking: Can I take melatonin while pregnant? Here, we break down all you need to know about melatonin and pregnancy, from melatonin safety to its efficacy.

What is melatonin?

Melatonin is a hormone released by the pineal gland, which is a teeny-tiny endocrine gland in the brain. Melatonin’s primary duty is to regulate your sleep-wake cycle. “Melatonin gets naturally released in your body when the lights dim, which signals that bedtime is near,” explains Dr. Harvey Karp, sleep expert and author of The Happiest Baby on the Block.  On the flip side, melatonin production decreases when it’s light, which signals the brain to perk up. (Learn how morning light and evening darkness keeps melatonin in check.)

The melatonin supplements you can buy over-the-counter at your local drugstore are usually synthetic melatonin and it’s thought that they may help with jet lag, delayed sleep-wake phase disorder, and some pediatric sleep issues. “But that doesn’t mean that melatonin is a sleeping pill,” says Dr. Karp. Instead, melatonin can put you into a state of quiet wakefulness that can help promote sleep.

Is melatonin safe during pregnancy?

The short answer to Is melatonin safe for pregnancy? is…we don’t know for sure. Animal studies have shown that taking melatonin in pregnancy can negatively affect birth weight and size—and mortality rates—but those results have not been replicated in human studies.

Currently there is not enough evidence to whole-heartedly state that taking melatonin in pregnancy is safe. What some experts do say, however, is that melatonin during pregnancy is “probably safe.” Of course, “probably safe,” does not mean you should haphazardly pop melatonin supplements during pregnancy. If you’re pregnant or nursing, it’s “especially important” to consult your healthcare provider before taking any medication or supplements, including melatonin, advises the National Center for Complementary and Integrative Health (NCCIH).

Will melatonin help with pregnancy insomnia?

It’s not recommended. Beyond any possible safety concerns, there’s not enough strong evidence that finds melatonin is an effective treatment for chronic insomnia in pregnancy or otherwise, according to the NCCIH. Learn more about pregnancy insomnia and melatonin’s role in the condition.

Who should take melatonin in pregnancy?

Sometimes doctors may suggest melatonin supplements to those with preeclampsia…for reasons unrelated to sleep. That’s because melatonin has shown to help reduce oxidative stress within the cells of the placenta, according to research in the International Journal of Molecular Sciences. Still, don’t start taking melatonin without speaking with your care team first.

Does melatonin cross the placenta?

Yes. Evidence shows that melatonin crosses the placenta quickly and easily, which suggests that taking melatonin in pregnancy may impact your unborn baby. The exact effect is still unknown. But since your naturally occurring melatonin is thought to help train the circadian rhythms in your baby-to-be, there’s a possibility that melatonin supplements may potentially impact sleeping patterns after birth.

Melatonin and Pregnancy: Supplement Smarts

While melatonin requires a prescription in several countries, in America, melatonin is considered a dietary supplement. Because of that, melatonin is not subjected to the same safety and efficacy standards as prescription or over-the-counter drugs. This is why it's important to know that…

  • Melatonin labels may be inaccurate. Studies have shown that most melatonin supplements did not contain the amount of melatonin that was listed on the label. Plus, 26% contained the hormone serotonin, which can have harmful effects even at low doses.

  • Melatonin doesn’t mix with certain meds. Melatonin might increase the risk of bleeding in folks taking blood thinners. It may also prove dangerous to take melatonin if you’re taking blood pressure or diabetes medication, some antidepressants, anticonvulsants for epilepsy, certain anxiety medications, among others.

  • Melatonin doesn’t have a set dose. The serving sizes on melatonin labels aren’t based on FDA recommendations. Melatonin is typically sold in doses ranging from 0.3 to 20 milligrams, with some even stretching up to 60 milligrams per dose. But the truth is, most people should not take any more than a 3-milligram dose of melatonin, according to the Sleep Foundation! While you likely won’t overdose on melatonin, you may experience unpleasant side effects.

  • Melatonin has side effects. Melatonin can cause headache, dizziness, and nausea—so if you’re already experiencing these symptoms in pregnancy, melatonin is likely not a wise move. Less common side effects include mild tremors, mild anxiety, abdominal cramps, irritability, or confusion. Some people report increased nightmares or vivid dreams, too.

  • Avoid melatonin if you have an autoimmune disease. Melatonin may exacerbate certain autoimmune conditions by stimulating the immune response.

Melatonin and Pregnancy: The Bottom Line

If you are having trouble sleeping during pregnancy, melatonin “may not be the best course of action,” according to the Sleep Foundation. The organization states that “most people who take melatonin don’t need it.” For better sleep in pregnancy, it’s a better idea to revamp your sleep hygiene and follow science-backed sleep tips. If you’re suffering from pregnancy insomnia, reach out to your care provider to learn about cognitive behavioral therapy for insomnia (CBT-I). Studies show that CBT-I can help ease insomnia and improve sleep for pregnant people. And for help with sleep after Baby arrives, consider SNOO! SNOO is a responsive bassinet that has been shown to add up to 2 hours of sleep a night for babies and their tired parents. Learn more about SNOO.

More on Sleep:




  • Sleep Problems in Pregnancy-A Cross-Sectional Study in over 7000 Pregnant Women in Poland. International Journal of Environmental Research and Public Health. July 2020
  • American College of Gynecologists and Obstetricians (ACOG): Sleep Health and Disorders
  • National Center for Complementary and Integrative Health (NCCIH): Melatonin: What You Need To Know
  • Johns Hopkins Medicine: Melatonin for Sleep: Does It Work?
  • Effect of melatonin supplementation on pregnancy outcome in Wistar-Kyoto and Sprague-Dawley rats. Acta Physiologica Sinica.April 2013
  • Sleep Fpoundation: Can You Take Melatonin While Pregnant?
  • Melatonin use during pregnancy and lactation: A scoping review of human studies. Brazilian Journal of Psychiatry. May-June 2022
  • Melatonin Promotes Uterine and Placental Health: Potential Molecular Mechanisms. International Journal of Molecular Sciences. December 2019
  • Perinatal Use of Melatonin for Offspring Health: Focus on Cardiovascular and Neurological Diseases. International Journal of Molecular Sciences. October 2019
  • Mayo Clinic: Melatonin
  • Sleep Foundation: How Much Melatonin Do We Really Take?
  • Sleep Foundation: Pregnancy Insomnia: Causes & Treatment

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Disclaimer: The information on our site is NOT medical advice for any specific person or condition. It is only meant as general information. If you have any medical questions and concerns about your child or yourself, please contact your health provider.