Sleep, hormones and our periods

Everyone keeps telling us that getting good-quality sleep is essential for our health, but today I want to explore why that is. What actually happens in our bodies when we don’t get enough sleep? How do our hormones react? And why can a lack of sleep impact our menstrual cycle?

Let’s take a deeper look at the effects of poor sleep when it becomes a regular pattern.

According to the International Classification of Sleep Disorders (ICSD-3), insufficient sleep is defined as consistently getting less sleep than needed for at least three months, resulting in daytime sleepiness (1).

Sleep is one of our body’s fundamental functions. To function well throughout the day, we need sleep to recover and recharge. As a crucial bodily function, sleep also impacts our two master hormones: cortisol and insulin.

Cortisol, known as the stress hormone, is released when our body goes into fight-or-flight mode. It temporarily suppresses main functions like digestion, sleep, and reproduction to help us survive. Cortisol is influenced by both the timing and quality of our sleep, and here’s where the negative feedback loop comes into play: stress increases cortisol levels, which disrupts sleep, and the lack of sleep keeps cortisol elevated. This, in turn, makes it harder to relax and recover, creating a cycle that negatively affects our entire system.

Sleep also affects insulin, the hormone responsible for regulating our blood sugar levels. Cortisol, during stress or lack of sleep, lowers insulin levels to give our body quick access to sugar for energy in case we need to fight or flee. If that sugar isn’t used up, insulin levels rise again to regulate it. This can make our metabolism work harder, which is one reason why poor sleep is linked to obesity and diabetes (2).

What’s the connection to our menstrual cycle?

Cortisol and insulin are the master hormones, and our sex hormones depend on them. Our sex hormones sit at the bottom of the hormonal hierarchy, so they inevitably get impacted by disruptions in the levels of cortisol and insulin.

Chronic sleep deprivation can lead to persistent stress (2), and if cortisol is out of balance, it may cause an overproduction of estrogen, potentially leading to heavy menstrual bleeding or other imbalances. (3)

Furthermore, lack of sleep can exacerbate symptoms of premenstrual syndrome (PMS), leading to mood swings, cramps, and other unpleasant effects on your period. (3)

Why is this important?

The good news is that our menstrual cycle can actually serve as a reflection of our overall health. Those of us who menstruate have a unique advantage: we can use our cycle as a fifth vital sign, a signal that tells us how well we’re managing our health. However, we often don’t realize we’re sleep-deprived, whether it's from late-night work or carving out “me-time” at the expense of sleep. We too often adjust our sleep to fit in with everything else we need to do during the day.

What if we reversed this? What if we prioritized our sleep and organized our day around it instead? Getting to bed earlier and incorporating power naps (an incredible hack to boost energy and creativity, by the way!) could change everything.

Personally, I love sleep. Although my sleep was disrupted for years due to a poor lifestyle and later, my kids, I’ve always made it a priority. Over time, I’ve learned to protect my sleep using various techniques.

So, what constitutes good-quality sleep?

A good night’s sleep typically lasts between 7 to 9 hours, with the ability to stay asleep through the night. This is largely regulated by melatonin, our sleep hormone, which is closely linked to our circadian rhythm—the natural day-night cycle. Disrupting this rhythm, such as by going to bed too late regularly, can make it harder to stay asleep throughout the night. Additionally, melatonin is influenced by your sleep routine, so establishing consistent sleep habits can significantly improve your sleep quality.

Lack of sleep is also linked to an increased risk of mortality, along with the negative effects on mental and physical health. In fact, it's now considered an epidemic, partially due to the rise of screen time (2).

Tips for Improving Sleep Quality:

• Turn off screens 1-2 hours before bed, or wear blue light-blocking glasses.

• Keep your phone off, ideally in another room.

• Create a sleep ritual: Read a non-work-related book, meditate, or journal to reflect on your day.

• Avoid drinking water 1-2 hours before bed.

• Don't eat right before going to bed.

• Drink less than 4 units of alcohol per week

Changing habits can feel challenging, but one approach is to take baby steps and not judge yourself for not doing everything perfectly. For example, I still watch a show an hour before bed—but by acknowledging our habits and focusing on improving them, we gradually make progress.

Have fun creating your new sleep routine, and remember: a restful night’s sleep is one of the best ways to support your health. 🌙

References:

(1)    The Global Problem of Insufficient Sleep and Its Serious Public Health Implications, Vijay Kumar Chattu et al, Healthcare MDPI, 2018: https://pmc.ncbi.nlm.nih.gov/articles/PMC6473877/

(2)     Role of Sleep and Sleep Loss in Hormonal Release and Metabolism, Leproult et al, Endocr Dev, 2011: https://pmc.ncbi.nlm.nih.gov/articles/PMC3065172/

(3)   Menstrual disturbances and its association with sleep disturbances: a systematic review, Jeon et al, BMC Women's Health, 2023: https://pmc.ncbi.nlm.nih.gov/articles/PMC10474748/