Reviewed by Dr. Kenton Bruice, MD
Reading time: three minutes
Many women in their 30s and 40s are surprised to find their sleep changing in ways they cannot explain. It can feel like it happens overnight—suddenly you are waking up at 2 or 3 a.m., overheated or alert, and unable to fall back asleep. By morning, you feel worn out and need a midday nap to function.
These disruptions are not just a normal part of getting older. For many women, they are an early sign of perimenopause. Hormonal shifts during this transition can affect temperature regulation, stress hormones, and the brain chemicals that support sleep.
In this blog, you will learn why sleep becomes so unpredictable, what factors can make it worse, and which approaches can help you get more consistent rest.
Table of Contents
Key Takeaway
Hormone changes in perimenopause often disrupt sleep, leaving you exhausted and frustrated. With the right support, including targeted lifestyle strategies and bioidentical hormone therapy, it is possible to restore more restful, consistent sleep and improve your overall well-being.
Hormone Fluctuations: The Real Reason Sleep Goes Haywire
Perimenopause is a hormonal rollercoaster. Estrogen and progesterone do not simply decline, they spike and drop unpredictably, and that throws your brain and body into chaos.
Here is how hormonal changes affect sleep:
- Low progesterone makes it harder to stay asleep. Progesterone supports GABA, a neurotransmitter that helps your brain relax and settle into deeper sleep.
- Fluctuating estrogen can trigger hot flashes and night sweats, causing frequent waking and interrupting REM sleep.
- Shifting hormone levels can interfere with melatonin production, making your sleep-wake cycle less predictable
Over time, these changes can lead to early waking, trouble falling back asleep, and nights that never feel truly restorative.
Cortisol and Blood Sugar: The Hidden Sleep Disrupters
Even when hormone fluctuations are the main driver, other factors can add to the problem:
- Elevated nighttime cortisol, often from chronic stress or overexercising, can keep your brain alert and make it hard to stay asleep.
- Blood sugar drops during the night can trigger a surge of cortisol, leading to sudden waking.
- Reduced metabolic flexibility, which is common in perimenopause, makes your body less able to handle these swings and increases the risk of fragmented sleep.
These shifts commonly contribute to early-morning awakenings, particularly between 2 and 4 a.m.
What You Can Try First: Non-Hormonal Sleep Support
Many women find relief by starting with these practical, research-backed strategies:
- Adjust meal timing. Eat your last meal at least three hours before bed, and avoid sugar or alcohol in the evening to help keep blood sugar and cortisol levels steady overnight.
- Support your circadian rhythm. Use blackout curtains, limit screens or wear blue-light-blocking glasses after sunset, and stick to a consistent bedtime.
- Balance exercise with recovery. High-intensity workouts can improve sleep when done earlier in the day, but training late in the evening or pushing too hard during stressful periods may disrupt sleep.
- Consider targeted supplements. Magnesium glycinate or L-theanine may help promote relaxation and make it easier to unwind before bed.
- Explore cognitive behavioral therapy for insomnia (CBT-I). This structured approach is proven to improve sleep quality and reduce the stress that fuels insomnia.
While these changes can make a meaningful difference, they may not fully resolve sleep issues linked to hormone imbalance. If sleep remains disrupted, additional support may be necessary.
When to Consider Hormone Replacement Therapy
If your sleep has been disrupted for months, even after improving sleep habits and nutrition, it may be time to look deeper.
Hormone replacement therapy can help:
- Stabilize estrogen and progesterone levels to reduce night sweats and early waking
- Rebalance the brain-body connection that supports healthy sleep cycles
- Support mood, energy, and overall well-being throughout the day
Dr. Bruice tailors each treatment plan based on comprehensive lab work, including hormone panels and other tests to understand your unique physiology.
Learn More About Hormonal Imbalance and Hormone Testing
When to Talk to a Specialist
If your sleep has become unpredictable or you find yourself dreading bedtime because you know you will wake up unrested, it may be time to speak with a provider who can look at the full picture.
A hormone-informed approach can help you move past trial-and-error strategies and work toward more consistent, restorative sleep.
Schedule a Consultation in St. Louis
At the St. Louis Hormone Institute of Missouri, Dr. Kenton Bruice specializes in bioidentical hormone replacement therapy to address the full spectrum of perimenopausal symptoms. An in-person consultation in St. Louis includes a comprehensive hormone evaluation and a personalized treatment plan.
To book an appointment with Dr. Bruice at the St. Louis Hormone Institute of Missouri, call (314) 222-7567 or visit us at 9909 Clayton Rd, Suite 225, St. Louis, MO.
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