For decades, the conversation about better sleep has followed a familiar formula. Keep your bedroom cool, avoid screens before bed, maintain a consistent schedule, and perhaps invest in a better mattress. More recently, technology has introduced another layer: sleep scores, recovery metrics, heart rate variability and increasingly sophisticated systems designed to optimise every hour spent in bed.

But there is a problem with the assumption that sleep can be improved through a relatively fixed set of rules. Our bodies don't remain the same throughout our lives, and neither do their requirements. For women, hormonal changes can significantly alter everything from temperature regulation to sleep continuity, sometimes making a previously comfortable sleeping environment feel completely unsuitable.

This is the question Eight Sleep has been exploring through its Women's Sleep Initiative, which has analysed more than three million hours of women's sleep. The company's latest development, Menopause Mode, is designed to address temperature-related sleep disruption during perimenopause, menopause and postmenopause. But the research behind it reveals something more interesting than another technological feature: how much conventional approaches to sleep have overlooked the physiological differences between people.

We tend to think of our preferred sleeping temperature as a personal constant. Some people like a cold bedroom, others prefer a warmer one, and couples frequently disagree about the correct setting for the air conditioning. Once you have found a comfortable temperature, the assumption is that you should simply stick with it.

According to Alexandra Zatarain, co-founder of Eight Sleep, the company's research challenged precisely this idea.

"The biggest surprise was how much a woman's temperature moves across her life. In a study of 1,884 women, we saw roughly a 5°F spread in preferred bed temperature across hormonal life stages," she explains.

The difference is approximately 2.8°C, and it isn't simply a matter of individual preference. The study also found that women using hormone replacement therapy preferred bed temperatures around 1.5°F warmer than those who weren't receiving it. Women in their third trimester of pregnancy, meanwhile, were among those selecting the coolest settings.

For Eight Sleep, these findings prompted a reassessment of how personalised temperature control should work.

"We had designed around the idea that each person has an ideal temperature you find once and keep. For many women, that number keeps moving," Zatarain says. "So the job isn't to find your temperature. It is to keep up with it."

It is an important distinction. Rather than treating personalisation as a one-time adjustment, it suggests that sleeping environments may need to respond to changes occurring over months, years and different stages of life.

Menopause is frequently associated with hot flashes and night sweats, but the relationship between hormonal changes and sleep is considerably more complicated than simply feeling too warm.

Oestrogen plays a role in the brain's regulation of body temperature. During the menopause transition, hormonal fluctuations can narrow the body's thermoneutral zone, the range of internal temperatures within which it can remain comfortable without triggering additional cooling or warming responses.

As a result, relatively small changes in core temperature may provoke a disproportionate reaction, including flushing, sweating and an increased heart rate. When this happens during sleep, the disruption can extend beyond the hot flash itself. A woman may wake up sweating, subsequently feel cold and struggle to fall asleep again.

"The sleep environment matters too," Zatarain explains. "Many mattresses and duvets hold heat close to the body right when it is trying to release it, and that is the part we can act on."

However, temperature isn't necessarily responsible for every sleep problem associated with menopause. Hormonal changes may also influence sleep directly, and researchers are still investigating why symptoms vary so dramatically between women.

"Researchers don't fully understand why some women have hot flashes for a year or two and others for more than a decade," Zatarain says. "It isn't clear how much menopausal sleep loss comes from hot flashes and how much from hormones acting on sleep directly."

That uncertainty matters. It means that improving the sleeping environment may address one important source of discomfort without resolving every cause of disrupted sleep.

Eight Sleep's Pod is a temperature-regulating sleep system that fits over an existing mattress. It can heat or cool each side of the bed independently and monitor sleep without requiring a wearable device.

Its newly introduced Menopause Mode takes a more targeted approach to temperature regulation. Rather than maintaining one setting throughout the night, the system adjusts cooling according to patterns identified in the company's research and the individual user's preferences.

The initial adjustments were developed using more than 57,000 nights of sleep data collected from 450 perimenopausal and postmenopausal women. By identifying periods of the night when hot flashes were more frequently reported, Eight Sleep developed a system that lowers bed temperature ahead of those periods.

"It starts with a population pattern," Zatarain explains. "From there it becomes personal. Autopilot learns the temperatures she actually chooses and adjusts for her room and the season, so her settings follow her as her needs change."

This doesn't mean the technology can predict exactly when an individual hot flash will occur. The approach is based on population-level patterns and personalised temperature preferences rather than direct detection of an impending episode.

For unexpected symptoms, the system also offers Rapid Cooling, which allows users to activate additional cooling using a physical button on the bed or through the app.

"No prediction will catch every hot flash," Zatarain acknowledges. "The idea is that the Pod does the adapting, so she doesn't have to."

The distinction between anticipating a likely period of discomfort and accurately predicting a physiological event is important, particularly as health technology increasingly adopts the language of artificial intelligence and predictive personalisation.

Eight Sleep's announcement includes a particularly striking figure: a reported 56% reduction in nighttime hot flashes when participants used the Pod's temperature control.

But percentages are only meaningful when we understand what was measured.

According to Zatarain, the finding comes from a 14-night crossover study involving 98 perimenopausal and postmenopausal women. Participants spent one week sleeping with the Pod's temperature control switched off and another with it enabled, reporting their nighttime hot flashes each morning.

On average, participants reported 56% fewer nighttime hot flashes during the temperature-control week, while 85% experienced a reduction.

These results are promising, but they aren’t the same as demonstrating a long-term clinical benefit. The study lasted only two weeks, relied on self-reported symptoms and can’t establish whether the improvements would persist over months or years.

"Like any first study, it has limits," Zatarain says. "It covered two weeks, and hot flashes were self-reported, so it speaks to short-term change. Long-term outcomes need more work."

The company is planning further research involving longer observation periods, more objective measurements and broader participant groups.

There is also a distinction between reducing nighttime discomfort and treating menopause itself. Temperature regulation may help manage symptoms, but it doesn’t address the underlying hormonal transition or replace medical assessment and treatment when these are needed.

The modern sleep industry has developed a particular vocabulary. We talk about optimisation, efficiency, recovery, deep sleep percentages and performance scores. Sleep has increasingly become something to measure, improve and occasionally compete over.

For people navigating persistent sleep disruption, however, these ambitions can feel rather detached from reality.

"For a long time our story was about performance: more deep sleep, better recovery, a higher score," Zatarain says. "For a woman in perimenopause, though, good sleep often means getting through the night without waking up soaked at 3 am, sharing a duvet with her partner again, and having a normal day afterwards."

It is a useful reminder that the purpose of sleep technology shouldn't necessarily be to produce increasingly impressive data. Sometimes the most meaningful improvement is simply the absence of a problem that has become part of everyday life.

The challenge, of course, is that personalised technology often introduces additional responsibilities for its users. More information means more opportunities to monitor, compare and worry about our bodies.

Eight Sleep's approach attempts to reduce that burden through automatic adjustments. Users can review their sleep patterns, log symptoms and examine changes associated with factors such as hormone therapy or alcohol consumption, but these features are optional.

"I think tracking fatigue comes from data that hands you a problem and leaves you to solve it," Zatarain explains. "Good personalisation should take decisions off her plate. If a woman never opens the app and simply sleeps better, that counts as a success."

It is a particularly relevant point for an industry that has spent years encouraging people to become amateur analysts of their own sleep.

Menopause Mode follows the introduction of Eight Sleep's Pregnancy Mode earlier in 2026. Both developments reflect a broader shift in the company's approach to product design, one that recognises how physiological needs change throughout life.

The cultural significance of this shift extends beyond sleep technology.

Women's health has historically received less research attention than many other areas of medicine, while experiences such as menopause have frequently been treated as private inconveniences rather than legitimate subjects of scientific and technological development.

"Menopause still gets treated as a punchline, or as an ending, when for most women it lands in the middle of their working and family lives," Zatarain observes.

This lack of attention has practical consequences. Symptoms may go unrecognised, women may struggle to connect changes in their sleep with perimenopause, and products developed around supposedly universal needs may fail to account for significant physiological differences.

For Zatarain, the solution begins with abandoning the idea of a single average sleeper.

"Many sleep products are designed around an average sleeper who doesn't really exist," she says. "For a long time women have been asked to adapt to products. We would like products to adapt to women."

Menopause Mode began rolling out globally on October 29, 2026 and is available to Eight Sleep Pod owners with an active Autopilot membership.

Whether its reported short-term benefits translate into sustained improvements will require further independent and long-term investigation. But the broader question it raises is already worth considering.

Perhaps the future of sleep technology isn't about finding one perfect routine, temperature or score. Perhaps it is about recognising that the person going to bed tonight isn't necessarily the same person, physiologically speaking, who went to bed ten years ago.

And that shouldn't be a problem the sleeper is expected to solve alone.