Progesterone & GABA: A Hormonal Key to Restful Sleep

Some sleep issues aren’t just about stress—or even about sleep itself. They might have more to do with hormones than you think. One of the quiet but powerful players in this realm is progesterone, and its deeply calming companion, GABA.

If you’ve been feeling tired but wired and can’t fall asleep, or waking up around 2–4am, or noticing that your mood and cycle are shifting, then this may be part of the picture.

What is Progesterone, Really?

Progesterone is most known for its role in fertility and reproduction, but its impact stretches far beyond that. It plays a key role in regulating mood, supporting deep sleep, and calming the nervous system.

In menstruating women, progesterone rises after ovulation, in the second half of the cycle (the luteal phase). It prepares the uterus for possible pregnancy, yes, but it also has profound effects on the brain. This is when we feel more inward, quieter, and ideally, more able to rest.

But if ovulation doesn’t happen, or if progesterone production is low, that quiet calm may not come. Instead, we may feel anxious, edgy, weepy, or wired at night. That’s why low progesterone is often linked to PMS symptoms like insomnia, irritability, and breast tenderness.

"Without ovulation, there is no progesterone. Without progesterone, sleep becomes more fragile, and women may experience symptoms such as irritability, insomnia, anxiety, breast tenderness, and bloating." — The Deep Blue Sleep book

Perimenopause, Menopause, and the Loss of Progesterone

As women enter perimenopause, progesterone is usually the first hormone to drop. It doesn’t happen all at once—it’s a gradual, uneven winding down. Some cycles are ovulatory, others not. And as ovulation becomes less regular, progesterone production decreases.

During menopause, when ovulation has ceased altogether, progesterone remains low. This is why many women report changes in sleep, mood, and emotional resilience, not just due to life stress, but from the absence of this naturally calming hormone.

GABA is key here, too. The reduction in progesterone means less natural support for GABA, one of your nervous system's internal soothing neurotransmitters. Without that support, the night can feel “louder”, more difficult to navigate.

How Progesterone Boosts GABA

One of the most fascinating things about progesterone is how it interacts with GABA (gamma-aminobutyric acid), a neurotransmitter that helps calm brain activity.

"Progesterone has a calming effect because it enhances the effect of the neurotransmitter GABA, one of the main inhibitory neurotransmitters." — The Deep Blue Sleep book

GABA is often called the brain’s "brake pedal." It helps us feel centered, grounded, and able to let go. And progesterone amplifies GABA’s effects, acting like a natural anti-anxiety agent.

So when progesterone drops, our GABA levels, and their calming influence, may drop too. This helps explain why so many women in perimenopause and menopause feel more anxious or wired, even when nothing else has changed.

In this way, progesterone isn’t just a reproductive hormone—it’s a nervous system ally.

Testing for Clarity: DUTCH and Neurotransmitters

If this all sounds like it might be relevant to your experience, we can explore it further with testing.

For hormones like progesterone, I often recommend the DUTCH test, a comprehensive dried urine test that gives us a full picture of hormone levels and how they’re metabolized. It’s useful not just for cycling women, but also for those in menopause.

For neurotransmitters like GABA, we can do urinary neurotransmitter testing, which offers insight into the balance of calming and activating chemicals in your system. These tests aren’t diagnostic, but they can be incredibly helpful in understanding patterns—and guiding treatment.

A Note on Men and GABA

Though this piece focuses on women, men also produce progesterone—and can feel its calming effects. Chronic stress, poor sleep, and aging can lower levels, too. If this resonates, no matter your gender, you’re not excluded from this story.

You’re Not Alone in This Sleep Journey

I’ve worked with so many women—some who are navigating sleeplessness for the first time, others who’ve tried everything and still can’t rest. What I’ve seen is this: when we support the hormonal system and nervous system together, sleep often returns. Gently. Gradually. And in a way that feels aligned with your unique body.

💛 Book a free 30-minute consult if this speaks to you (Boulder or virtual support available)
📘 And for a more grounded, self paced guide to sleep, check out my book The Deep Blue Sleep—available in paperback, ebook, and audiobook.