Melatonin & Fertility: Your Sleep Hormone's Surprising Role in Reproductive Health

Let's talk about that other supplement you've seen popping up in TTC forums—not for egg quality, but for sleep... or maybe both?

If you're on the fertility journey, melatonin might not be the first thing you think of when building your supplement stack. But this nighttime hormone has been gaining attention in the fertility world—not just for better ZZZs, but for its potential impact on egg quality and IVF outcomes.

So let's unpack what melatonin really does, how it works in your reproductive system, and whether it deserves a spot in your fertility toolbox.

Wait—Isn't Melatonin Just a Sleep Aid?

Yes—and no.

Melatonin is best known as the hormone that helps regulate your sleep-wake cycle (aka circadian rhythm). Your brain naturally produces it when it gets dark, signaling your body that it's time to wind down and rest.

But here's where it gets interesting: melatonin is also produced in your ovaries, where it acts as a powerful antioxidant—one that protects your eggs from oxidative stress. In fact, some researchers are calling it a "guardian of oocyte quality."

Melatonin and Your Eggs: What's the Connection?

Just like resveratrol, melatonin has antioxidant properties. But unlike resveratrol, it's already naturally present in the follicular fluid surrounding your eggs.

Studies have shown that higher melatonin levels in this fluid are linked to better oocyte quality, stronger embryo development, and higher fertilization rates.

Here's how melatonin may support fertility:

✅ Scavenges free radicals that can damage egg cells

✅ Protects mitochondrial DNA and improves energy production in oocytes

✅ Enhances progesterone production in the luteal phase

✅ May improve outcomes in IVF by improving egg maturation and embryo quality

Some clinical trials have shown that melatonin supplementation could lead to more mature eggs and higher fertilization rates in IVF, but it’s important to remember that these findings are still under study and not all outcomes are universally agreed upon.

Melatonin for IVF: A Secret Weapon?

Melatonin is increasingly being studied in IVF settings. Some clinics are now recommending it during ovarian stimulation for those with poor egg quality or diminished ovarian reserve.

In clinical studies, melatonin supplementation (usually between 2mg–6mg per day) was associated with:

🔹 Improved oocyte quality

🔹 Higher fertilization rates

🔹 Better embryo development

🔹 Potential increase in pregnancy rates (though this remains debated)

It's not a magic bullet—but it could be a supportive player, especially for those dealing with oxidative stress or undergoing multiple IVF rounds.

What About Natural Conception?

If you're TTC naturally, melatonin might still offer some benefit—especially if:

🌙 You're not sleeping well (sleep disorders, night shift work, irregular cycles)

🌙 You're over 35 and want to optimize egg quality

🌙 You're exposed to blue light and environmental stressors that suppress melatonin production

Healthy sleep is essential for regulating hormones, supporting ovulation, and maintaining a healthy luteal phase. However, sleep disruption can affect fertility, so supporting sleep may benefit your overall cycle.

In other words—prioritizing melatonin may support more than just your sleep. That said, melatonin is still a hormone, and its effects on natural conception aren't fully understood. Some experts, like Rebecca Fett, have warned that melatonin might interfere with ovulation if taken at the wrong time in the cycle, potentially delaying key hormonal surges.

How Much Should You Take?

Most studies on melatonin and fertility use doses between 2mg–6mg, usually taken in the evening. However, lower doses (0.3mg–1mg) may also be effective for sleep regulation with fewer side effects like grogginess or vivid dreams.

🛑 Important note: Melatonin is a hormone, and long-term use at high doses hasn't been studied extensively for fertility. More isn't always better.

If you're TTC, especially through IVF, talk to your fertility specialist before adding melatonin to your routine.

Can Melatonin Harm Fertility?

For the most part, melatonin is considered safe and non-toxic. But there are a few things to keep in mind:

⚠️ It can interfere with ovulation if taken at the wrong time in the cycle

⚠️ It might delay LH surge in some individuals

⚠️ It may not be ideal for women with certain hormone-sensitive conditions

Some researchers suggest stopping melatonin during the luteal phase (after ovulation) to avoid potential interference with implantation and progesterone signaling.

Natural Ways to Boost Melatonin

Not sure about supplements? You can also support your body's melatonin production naturally:

🌘 Dim lights in the evening

📵 Avoid screens 1–2 hours before bed

🕯️ Try red or amber lighting at night or get blue light blocking glasses

😴 Keep a regular bedtime and wake time

The Bottom Line: Sleep on It (Literally)

Melatonin may be a helpful addition to your fertility plan; it’s especially promising for IVF prep or those with diminished ovarian reserve.

But like any supplement, it’s important to use it strategically:

👍 May help: Egg quality, oxidative stress, sleep support, IVF prep

👎 May harm: Ovulation timing, implantation (if used at wrong time)

Talk to your provider about timing, dosage, and whether melatonin makes sense for your TTC journey.

References

1. Tamura H, Takasaki A, Taketani T, et al. The role of melatonin as an antioxidant in the follicle. J Ovarian Res. 2012;5(1):5.

2. Reiter RJ, Tan DX, Korkmaz A, et al. Melatonin and stable circadian rhythms optimize maternal, placental and fetal physiology. Hum Reprod Update. 2014;20(2):293-307.

3. Batıoğlu AS, Şahin U, Grlek B, et al. The efficacy of melatonin administration on oocyte quality. Gynecol Endocrinol. 2012;28(2):91-93.

4. Seko LM, Moroni RM, Leitão VM, et al. Melatonin supplementation during controlled ovarian stimulation for women undergoing assisted reproductive technology: systematic review and meta-analysis of randomized controlled trials. Fertil Steril. 2014;101(1):154-161.

5. Gooley JJ, Chamberlain K, Smith KA, et al. Exposure to room light before bedtime suppresses melatonin onset and shortens melatonin duration in humans. J Clin Endocrinol Metab. 2011;96(3).

6. Voordouw BC, Euser R, Verdonk RE, et al. Melatonin and melatonin-progestin combinations alter pituitary-ovarian function in women and can inhibit ovulation. J Clin Endocrinol Metab. 1992;74(1):108-117.