The Scientific Reason Why Women Need More Sleep Than Men

There is a familiar claim that women need more sleep than men because their brains work harder. It is an appealingly simple explanation, often accompanied by the suggestion that women require precisely 20 extra minutes each night. But the real science is both more nuanced and more useful.

Research does suggest that women often sleep slightly longer than men, while also being more likely to report insomnia, interrupted sleep and poor sleep quality. However, there is no official recommendation prescribing a fixed amount of additional sleep for every woman. Sleep needs vary according to age, health, hormones, pregnancy, stress, daily responsibilities and the quality of the sleep itself.

The most convincing explanation is not that every female brain requires a set number of extra minutes. Rather, women experience a combination of biological changes, circadian differences and social pressures that can increase their need for restorative sleep or make that sleep harder to obtain.

Understanding those influences can help women stop treating tiredness as something they simply have to tolerate and start giving sleep the attention it deserves.

For healthy adults, general sleep guidance is not divided by sex. The American Academy of Sleep Medicine and Sleep Research Society recommend that adults regularly obtain at least seven hours of sleep a night, with some people naturally needing eight or nine hours to feel their best. The recommendation applies to adults as individuals rather than prescribing separate targets for women and men. ( American Academy of Sleep Medicine)

Even so, studies measuring real-world sleep have repeatedly found differences between the sexes. A large wearable-technology study published in 2026 found that women slept an average of around 18 minutes longer than men, although there was considerable variation within both groups. ( PubMed)

Earlier research has reported similar patterns. In one population study of older adults, women slept about 16 minutes longer when sleep was measured objectively using wrist-worn monitors. Intriguingly, those same women believed that they slept less and rated their sleep as poorer than men did. ( Sleep study)

This tells us two important things. First, women may, on average, obtain slightly more sleep. Second, sleep duration does not necessarily equal sleep satisfaction. A woman can spend longer asleep yet still wake feeling unrefreshed because her rest has been fragmented, mistimed or disturbed by physical symptoms.

So, do women need more sleep? Some may. But the more accurate answer is that women are often exposed to more factors that disrupt sleep and increase recovery needs.

The idea that women universally need 20 additional minutes of sleep has been repeated so often that it is sometimes presented as settled medical advice. It is not.

The claim has commonly been linked to the suggestion that women use more areas of the brain during the day, perhaps because they are more likely to multitask. Sleep certainly supports memory, learning, emotional regulation and many other cognitive functions. However, there is not strong evidence that female brains, as a group, expend so much more effort through multitasking that every woman requires exactly 20 extra minutes in bed.

Recent findings showing an average difference of around 18 minutes may sound as though they confirm the rule. But an observed average is not the same as a biological prescription. Some women need considerably more sleep than the men around them; others need the same amount or less.

It is more helpful to think of 20 minutes as a rough population-level observation rather than a nightly target. Your own sleep requirement is better judged by whether you wake naturally, remain alert through the day and can function without regularly relying on caffeine or weekend lie-ins.

There is no single “female sleep switch”. Instead, several overlapping biological and lifestyle factors help explain why women and men can experience sleep differently.

Sleep is made up of several repeating stages, including light sleep, deep non-rapid eye movement sleep and rapid eye movement, or REM, sleep. Each stage supports different aspects of physical restoration, learning, memory and emotional wellbeing.

A 2024 scientific review found measurable sex differences in sleep and circadian regulation. Women tended to spend slightly longer in non-REM sleep and enter REM sleep earlier. The authors also noted that women may be more affected by extended wakefulness and circadian misalignment in some circumstances. ( Sleep Medicine Reviews)

This creates what researchers sometimes describe as a sleep paradox. Women can appear to sleep better according to objective measurements while simultaneously reporting worse sleep. Hormonal symptoms, pain, mood, repeated brief awakenings and the feeling of never fully switching off may all influence how restorative a night feels.

It also reminds us that good sleep is not simply a matter of clocking a particular number of hours. Continuity, timing and personal perception matter too.

The body’s internal clock helps determine when we feel awake and when sleepiness begins to arrive. Light is its most important external signal, but hormones, meals, activity and daily routines also help keep it aligned.

On average, women tend to show an earlier circadian timing than men. That may mean feeling sleepy earlier in the evening and being more inclined to wake earlier in the morning. The difference is modest and certainly does not describe everyone, but it can become relevant when daily life pushes bedtime later.

A woman who naturally becomes sleepy at 10pm but stays awake to finish work, complete household jobs or care for someone else may miss an especially useful window for falling asleep. If her body still wakes early, that lost time is difficult to recover.

This may be one reason why protecting the first signs of evening sleepiness can be so valuable. When your eyes feel heavy and concentration begins to soften, it may be wiser to start winding down than to treat the feeling as an inconvenience to overcome.

One of the clearest differences in women’s sleep is that it often changes across the reproductive lifespan. Fluctuations in oestrogen and progesterone interact with body temperature, mood and sleep regulation, while the physical symptoms accompanying different life stages can create additional disturbances.

Not every woman experiences significant hormonal sleep problems. However, for those who do, the effect can be substantial.

Some women notice little change in their sleep across the month. Others find it harder to fall asleep or stay asleep in the days before their period.

Premenstrual symptoms such as cramps, headaches, breast tenderness, digestive discomfort and changes in mood can make settling down more difficult. A rise in body temperature after ovulation may also feel uncomfortable for people who already sleep hot.

The US Office on Women’s Health notes that sleep difficulties can occur around the menstrual cycle, particularly during the days leading up to a period. ( Office on Women’s Health)

This does not necessarily mean that you need a completely different sleep routine each week. It may simply mean allowing yourself slightly more time in bed during difficult parts of the cycle, keeping the bedroom cool and recognising that tiredness is not a failure of discipline.

Tracking sleep alongside menstrual symptoms for two or three cycles can reveal patterns that are easy to miss from one day to the next.

Pregnancy can increase both sleepiness and sleep disruption. In early pregnancy, hormonal changes may leave some women feeling unusually tired. Later, finding a comfortable position can become harder, while backache, heartburn, leg cramps, foetal movement and more frequent trips to the bathroom may interrupt the night.

A pregnant woman may therefore spend plenty of time in bed without obtaining long, unbroken periods of rest. A greater sleep opportunity can help compensate for this fragmentation, although persistent exhaustion, loud snoring or breathing pauses should always be discussed with a midwife or doctor.

Sleep apnoea can emerge or become worse during pregnancy. It deserves proper assessment because it is not simply an ordinary part of feeling tired while expecting a baby.

After birth, sleep is shaped less by a neat biological schedule and more by the needs of a newborn. Feeding, soothing and checking on a baby can divide the night into short stretches, while physical recovery and hormonal changes add to the need for rest.

The familiar advice to “sleep when the baby sleeps” is not always realistic. Meals, washing, caring for other children and the simple desire to have a few quiet minutes can easily take priority. A more compassionate approach is to share night-time and early-morning duties wherever possible and treat practical support as part of postnatal health, not as a luxury.

Extreme tiredness, anxiety, persistent low mood or being unable to sleep even when there is an opportunity warrants professional support.

Sleep problems become particularly common during perimenopause and menopause. Changing hormone levels can coincide with hot flushes, night sweats, changes in mood and a greater risk of sleep apnoea.

Night sweats are an obvious source of disruption, but the relationship is not always straightforward. Some research suggests that waking can occur before the sensation of a hot flush, rather than the flush always causing the awakening. Either way, repeated disturbances can make it difficult to obtain restorative sleep.

The US National Institute on Aging recommends habits such as maintaining a regular schedule and seeking appropriate help for persistent sleep problems during the menopausal transition. ( National Institute on Aging)

Breathable nightwear, layered bedding and a comfortably cool room may make symptoms easier to manage, but severe or ongoing disruption deserves a conversation with a GP. Effective support is available, and poor sleep should not simply be accepted as an inevitable part of ageing.

Another important part of the picture is that women are more likely than men to experience insomnia.

A large meta-analysis found that women had a 41% higher risk of insomnia than men. A later analysis using formal diagnostic criteria also found a significantly higher prevalence among women. ( SLEEP, PMC)

This difference is not explained by hormones alone. Anxiety, depression, chronic pain and restless legs syndrome can all interfere with sleep and are reported more frequently among women in many populations. Caring responsibilities and the mental load of organising family life can also keep the mind active long after the lights go out.

Insomnia is more than the occasional restless night. It can involve regularly struggling to fall asleep, waking repeatedly, waking too early or feeling dissatisfied with sleep despite having a reasonable opportunity to rest.

When insomnia persists, spending ever longer in bed is not always the answer. Cognitive behavioural therapy for insomnia, known as CBT-I, is a recommended treatment that helps rebuild a healthier relationship between bed and sleep. A GP or qualified sleep professional can advise on suitable options.

Biology is only part of the scientific story. Gendered patterns of work, childcare and unpaid care can shape who has the opportunity to sleep.

Women are still more likely to provide unpaid care in the UK. Health Survey for England figures found that women were not only more likely to provide care but were also more likely to spend 20 or more hours a week doing it. ( NHS England Digital)

That responsibility does not necessarily end at bedtime. Listening for a child, supporting an older relative, anticipating the next day’s needs and remembering unfinished tasks can all create a state of low-level alertness.

The issue is sometimes described as women needing more sleep because they “do more”. That can sound judgemental or overly generalised. A better interpretation is that many women carry schedules that produce greater sleep debt while leaving fewer opportunities to repay it.

Practical redistribution can be more powerful than another elaborate bedtime ritual. Sharing night wakings, morning duties, planning and household work gives rest a genuine place in family life.

Most adult women should begin with the same evidence-based foundation as other adults: at least seven hours of regular sleep, with many feeling better closer to eight or nine.

The right amount is the amount that allows you to wake feeling reasonably restored and remain alert without struggling through the day. Your requirement may temporarily increase during pregnancy, illness, recovery from sleep loss or periods of intense physical and emotional demand.

Signs that you may need more or better-quality sleep include:

• Finding it extremely difficult to wake without an alarm
• Regularly needing long weekend lie-ins
• Feeling irritable, tearful or mentally foggy
• Struggling to concentrate or remember simple information
• Relying heavily on caffeine to remain functional
• Falling asleep unintentionally while reading, watching television or travelling
• Sleeping for a reasonable length of time but never feeling refreshed

A single tired morning tells you very little. Look for patterns across several weeks. A simple sleep diary can help you compare bedtime, waking time, menstrual symptoms, night sweats, caffeine, alcohol and daytime energy.

The scientific reason women may need more sleep than men is not one dramatic difference in the brain. It is the combined effect of sleep architecture, circadian timing, hormonal changes, pregnancy, menopause, insomnia risk and the realities of daily life.

Women do appear to sleep slightly longer on average, but there is no universal female requirement for exactly 20 extra minutes. The more valuable question is not whether you need more sleep than a man. It is whether you are obtaining enough uninterrupted, well-timed sleep for your own body.

If you wake refreshed and function well throughout the day, there is no need to chase an additional number. If you remain tired, however, take that message seriously. A slightly earlier night, a fairer sharing of responsibilities, a cooler bedroom or professional support may offer far more than simply pushing through until the weekend.

Good sleep is not indulgent downtime. It is a daily foundation for energy, emotional balance and wellbeing.