Menopause and Sleep - The Apeiron Life Perspective

8 min read

What it is:

Transitioning from regular menstrual cycles to menopause may begin around one's mid 40's and can last from a few years to several. Our early 50s is when one might generally reach menopause, but when it occurs and how long it may last is specific to the individual.

While a rare few ease into menopause without much trouble, most women report at least some symptoms, and these can be severe for an estimated 20% of the female population. Trouble sleeping often sits at the center of a constellation of problems. Hot flashes create a state of hyperarousal that makes it difficult to sleep, and sleep loss can worsen mood, cognition, and stress levels. While acceptance and compassion go a long way in alleviating menopause symptom distress, many practical tools can ease the transition and improve quality of life.

The purported claims:

Hormonal fluctuations during perimenopause can disrupt many physiologic processes, including sleep.
Once the transition to menopause occurs, the loss of sex hormones (estrogen and progesterone) increases the risk of obesity, hypertension, cardiovascular diseases, osteoporosis, sexual dysfunction, and some sleep disorders.
Lifestyle factors and hormone replacement therapy can alleviate discomfort and improve sleep quality.

What the science says:

Overview of the Menstrual Cycle

In young and early mid-life, prior to the onset of perimenopause, women experience the ebb and flow of several important sex hormones that facilitate the release of an egg from the ovary approximately every 28 days (Figure 1). The cycle begins on the first day of menstruation when the brain releases a steady stream of follicular stimulating hormone (FSH) and luteinizing hormone (LH) which act on the ovary to begin the maturation of a new egg follicle. This developing follicle releases estrogen, which feeds back onto the brain to release more FSH and LH until eventually, after approximately 14 days, the mature egg bursts from its follicle and travels down the fallopian tube into the uterus. If sperm are present, this is when a pregnancy can occur.

The egg sack left behind in the ovary (now known as the corpus luteum) starts to release progesterone and low estrogen levels for about a week or two. After this time, provided that the egg wasn’t fertilized, the corpus luteum shrivels up, estrogen and progesterone levels drop, and this triggers the uterus lining to shed, bringing about a new period that resets the cycle.

Female Sex Hormones and Sleep

There are cell receptors for estrogen and progesterone throughout the brain and body. These hormones play crucial roles in development, mood, energy levels, growth, cognition, sexual behavior, preventing hypertension and diabetes, regulating bone metabolism, and protecting neurons. They also support healthy sleep. While the research is relatively limited, studies have shown that during the follicular phase (between menstruation and ovulation), women tend to get more slow-wave (deep) sleep. In the luteal phase (between ovulation and the next period), women tend to have more sleep spindles (rapid bursts of neural activity associated with memory formation), less rapid eye movement (REM) sleep, and the REM sleep that does occur tends to start appearing earlier in the night.

Estrogen, which dominates during the follicular phase, is considered sleep-protective. It promotes consolidated sleep and shorter sleep onset. Progesterone, which dominates after ovulation, has an anti-anxiety effect through its binding activity with benzodiazepine receptors. It favors non-REM (NREM) sleep and also drives ventilation. This means that it lowers the risk of obstructive sleep apnea (OSA), which is caused by a narrowing of the airways during sleep and subsequent snoring and shallow breathing. The risk of OSA increases in postmenopausal women who no longer have high circulating progesterone levels.

Generally, premenopausal women report their best sleep around the time of ovulation and worst sleep right before or during menstruation. However, genetics, environmental factors, and a history of oral contraceptive use may result in different experiences. For example, the elevated progesterone accompanying the luteal phase is drowsiness-promoting, so it may induce deep sleep in one woman, while another may find these effects excessive, leading to daytime fatigue and irritability.

The individual needs highlight the importance of personalized healthcare in these scenarios.

How Menopause Affects Sleep

Perimenopause is almost always accompanied by hot flashes, which are sudden, intense feelings of warmth, flushing, and sweating. Hot flashes can last for several minutes or up to an hour or more and can appear at any time of the day or night. Some studies estimate that up to 70% of hot flashes are associated with sleep disturbances, which tend to disrupt non-REM, rather than REM, sleep. Hot flashes are thought to occur when low estrogen levels combine with elevated levels of norepinephrine to disrupt core body temperature regulation.

Core body temperature exhibits a circadian rhythm, with the lowest point occurring at night during sleep. This may be why hot flashes are so closely tied to sleep disturbances when the threshold is at its lowest. In premenopausal women, there is a natural increase in core body temperature of approximately 0.5-1.0°C during the luteal phase, driven by the rise in progesterone at this time. During the menopause transition, when estrogen and progesterone levels drop, this may further contribute to the development of hot flashes by lowering the core body temperature threshold even further.

In addition to the decrease in circulating estrogen and progesterone, menopause is accompanied by a decline in melatonin. While this drop in melatonin naturally occurs for both men and women with age, women may be uniquely vulnerable to the effects. There is a bidirectional relationship between melatonin and female sex hormones. Studies have shown that melatonin can interact with and alter FSH, LH, estrogen, and progesterone levels, but this varies among individuals and across the lifespan. Conversely, some studies have shown that circulating levels of these hormones can alter melatonin profiles. However, there is no established consensus on this, and more research needs to be done. Supplementing with melatonin at the onset of menopause can improve sleep for some women, but it is not guaranteed to work for everyone.

Circadian rhythms change during menopause, and women generally advance their sleep and wake times by about one hour. There can also be changes in cortisol patterns, particularly for women experiencing chronic stress. Under normal conditions, cortisol peaks in the morning to promote alertness upon waking. However, chronic stress can desynchronize this rhythm. This means that insufficient cortisol is released upon waking, leading to grogginess in the morning, and cortisol peaks in the afternoon or evening, promoting alertness during the “wind down” period and leading to subsequent sleep disturbances.

If sleep disturbances persist, this can cause anxiety or depression. While mood changes can occur independently of sleep loss, sleep disruption almost always makes things worse. By prioritizing better sleep, many other symptoms associated with menopause often improve.

The recommended first treatment for insomnia is Cognitive Behavioral Therapy for Insomnia (CBTi), as it has been shown to work well for women with menopause. In particular, doctors can work with patients to minimize the distress caused by hot flashes, which can empower and reduce symptom severity. In instances where CBTi doesn’t address the problem, sleep medications may be used, but it is helpful for physicians to consider genetic factors and lifestyle when tailoring treatments to patients.

Hormone Replacement Therapy & Other Treatments

Depending on symptom severity, at the start of menopause, some women may benefit from transition hormone replacement therapy (HRT). Unlike hormonal birth control, which suppresses natural circulating hormone levels in menstruating women, HRT helps restore what is lost during menopause. There is a widespread misconception that HRT increases the risk of breast cancer, but the evidence explicitly demonstrating this is limited. It has been shown that women on HRT at the time of a cancer diagnosis tend to have a much better prognosis than women not using HRT.

The numerous benefits associated with HRT appear to vastly outweigh the risks, but the timing of first use is key. Women who start HRT within 10 years of menopause generally have a lower risk of developing cardiovascular disease. However, it is important to note that HRT can increase the risk of blood clots, so speak to your doctor, especially if you have a family history. The risk of blood clots naturally increases with age, smoking, and weight gain. HRT may be protective against blood clots in some situations.

By putting back some of what is lost, HRT can significantly improve quality of life during the menopause transition. It can improve hot flashes, mood, sexual function, libido, energy levels, and sleep, as well as reduce the risk of fractures and hypertension. For those who experience sleep apnea after going through menopause, the progestins in HRT can improve breathing and reduce snoring.

As well as HRT, gabapentin has been found to alleviate hot flashes. Some data show that selective serotonin reuptake inhibitors (SSRIs) also aid hot flashes and mood disorders.

Modifying lifestyle factors can offer profound symptom relief. Phyto-estrogens are estrogen-mimicking compounds found in food sources, including soy. Isoflavones — the principal source of these soy phytoestrogens — may improve insomnia symptoms. Isoflavones are also found in hops and flax, but there isn’t yet any good evidence that these reduce sleep disturbances.

Currently, research on isoflavones does not have a consensus on the effects of certain illnesses, such as breast cancer. This may be due to the ability of isoflavones to exert both pro- and anti-carcinogenic factors. Speak with your doctor if you have any concerns.

In addition to increasing isoflavone intake, diets rich in polyunsaturated fatty acids (PUFAs) such as omega-3, fiber, and the amino acid tryptophan (which is used to make serotonin and melatonin) may improve health and may improve menopause symptoms. There are also many alternative therapies for menopause, such as transdermal estrogen patches. Yet, most of these are not regulated and have little or no data to support their efficacy and should be discussed with a trusted physician before use.

Our take:

Sex hormones are essential for so much more than just menstruation and pregnancy. Yet the research on the connection between female hormones, health, and disease risk is lacking. Every woman’s experience of menopause is different, with unique genetic profiles and lifestyle factors that may either help or hinder the transition. It is vital to work with healthcare professionals who view menopause holistically and can assist the change with the least amount of discomfort possible.

Will this benefit you?

While sleep disturbances in perimenopause are common for many women, this does not mean there aren't options. Suppose you are suffering from chronic sleep loss. In that case, a healthcare professional can assist with tools such as short-term medication, well-timed melatonin, adequate exercise, a balanced diet, mindfulness practices, and CBTi.

Some things to keep in mind:

As with many aspects of aging, menopause tends to be treated as something to live in fear of, with emphasis placed on loss and discomfort. However, there are many reasons that menopause can improve quality of life. Not having to experience menstruation and premenstrual syndrome can be immensely liberating. Plus, contraception is no longer required to prevent pregnancy. Once women have the tools to navigate menopause, they report a renewed sense of confidence and ease.

References and Further Reading:

Sleep in women across the lifespan - https://pubmed.ncbi.nlm.nih.gov/29679598/

Circadian rhythms, sleep, and the menstrual cycle - https://pubmed.ncbi.nlm.nih.gov/17383933/

Sleep in menopause - https://pubmed.ncbi.nlm.nih.gov/22288870/

Menopause review - https://pubmed.ncbi.nlm.nih.gov/18313505/

Management of menopause-related sleep disturbances - https://pubmed.ncbi.nlm.nih.gov/33253056/

Isoflavones (soy) and insomnia - https://pubmed.ncbi.nlm.nih.gov/20729765/

Progesterone effects on sleep - https://pubmed.ncbi.nlm.nih.gov/17168724/

Physiology of hot flashes - https://pubmed.ncbi.nlm.nih.gov/24012626/

Hot flashes and sleep - https://pubmed.ncbi.nlm.nih.gov/25256933/

Melatonin and sex hormones - https://pubmed.ncbi.nlm.nih.gov/33774638/

Insomnia treatments in menopause - https://pubmed.ncbi.nlm.nih.gov/32880197/