Poor sleep can affect male fertility. Research has linked sleep problems with lower sperm counts, reduced sperm concentration and changes in how well sperm move and develop. Sleep also helps regulate many of the processes involved in reproductive health.
That doesn’t mean a few late nights will make you infertile. Fertility is complicated, and sleep is just one part of the picture. But getting a good night’s sleep is another way to support your overall health and fertility.
How are sleep and male fertility connected?
While you sleep, your body is still busy. Sleep is closely connected with your circadian rhythm, or your body’s internal 24-hour clock. This helps regulate hormones, metabolism and many other processes throughout the body.
Researchers are increasingly interested in how disrupted sleep and circadian rhythms affect male reproductive health. A 2025 review of sleep and male fertility examined research on sleep disturbances, sperm quality, reproductive hormones and overall reproductive function. The researchers found growing evidence of a connection between sleep and male fertility.
So, long story short: Many things affect fertility, and sleep is one of them.
Can lack of sleep affect sperm quality?
Research suggests it can. A systematic review and meta-analysis looked at eight studies involving 2,169 men with sleep disorders and 3,858 men with normal sleep. Sleep disorders were associated with:
- a lower total sperm count.
- lower sperm concentration.
- reduced progressive motility, or the sperm’s ability to move forward.
- a lower percentage of normally shaped sperm.
More recent research has found similar results. A North American study looked at 690 men who provided 1,247 semen samples. Short and long sleep, frequent trouble sleeping and poor sleep quality were associated with lower sperm concentration, total sperm count and total motile sperm count.
Remember, an association doesn’t prove that poor sleep directly caused these changes. More research is still needed to understand exactly how sleep and sperm health are connected.
Read: 10 natural ways to increase your sperm count
How much sleep is best for sperm health?
There isn’t a magic number of hours that will guarantee healthy sperm. However, one study of 796 men found that semen volume and total sperm count were highest among men sleeping around seven to seven and a half hours a night. Both shorter and longer sleep were associated with lower results.
For example, men who reported sleeping more than nine hours had a 39.4% lower total sperm count than the seven to seven-and-a-half-hour group. Those sleeping six and a half hours or less had a 25.7% lower total sperm count, although the evidence for this group was less conclusive.
Rather than worrying about hitting an exact number every night, aim for regular, restful sleep that leaves you feeling refreshed.
Does sleep affect testosterone?
The link between sleep and testosterone isn’t quite as simple as it might seem. The systematic review found that sleep disorders were associated with several measures of poorer sperm quality. However, the researchers found no significant association with testosterone or the reproductive hormones FSH and LH.
Other research is continuing to explore the relationship between sleep, hormones and sperm production. A 2026 review suggests that disrupted sleep affects male reproductive health through several pathways, including inflammation, oxidative stress, hormone regulation and disruption to the body’s circadian rhythm.
So, while sleep and reproductive hormones are connected, it’s more complicated than getting less sleep and producing less testosterone.
Sleep apnoea and male fertility
Obstructive sleep apnoea causes breathing to repeatedly stop and start during sleep. This disrupts sleep and reduces the amount of oxygen the body receives.
A 2026 review of sleep disturbances and male reproductive health found that sleep apnoea and sleep deprivation affect reproductive function through changes involving hormones, oxidative stress and inflammation.
If you snore loudly, wake up gasping or choking, regularly wake with headaches, or feel very tired during the day despite getting enough sleep, it’s worth speaking with your doctor.
Does working shift work and having irregular sleep affect male fertility?
Night shifts and changing work schedules make regular sleep difficult. They also disrupt your circadian rhythm.
Research into shift work and male fertility is still developing. Studies in the systematic review examined factors such as night work, late bedtimes and poor sleep alongside semen quality. The researchers concluded that changes to circadian rhythms are one way sleep disorders affect male reproductive health.
If shift work is part of your life, focus on getting regular, good-quality sleep whenever your schedule allows.
How can I improve my sleep while trying to conceive?
You don’t need to completely change your routine overnight. A few simple habits can help you get more regular, restful sleep:
- Keep a regular sleep schedule. Try to go to bed and wake up at around the same time each day, including on weekends where possible.
- Give yourself enough time to sleep. Aim to leave enough time in your routine for a full night’s rest rather than regularly cutting your sleep short.
- Create a comfortable sleep environment. A cool, dark and quiet bedroom makes it easier to fall asleep and stay asleep.
- Watch your caffeine later in the day. Coffee, energy drinks and other sources of caffeine make it harder to fall asleep, particularly when consumed in the afternoon or evening.
- Wind down before bed. Give your body time to switch off with a relaxing routine, such as reading, showering or listening to something calming.
- Get some daylight and movement during the day. Regular physical activity and natural light help support your body clock and sleep.
- Pay attention to ongoing sleep problems. Regular trouble falling asleep, waking throughout the night, loud snoring, waking up gasping or feeling exhausted during the day are worth discussing with your GP.
Sleep is one part of the fertility picture
Poor sleep doesn’t mean you’ll experience infertility, and great sleep doesn’t guarantee healthy sperm. Research does suggest that sleep and male reproductive health appear to be connected. If you’re trying to conceive, looking after your sleep is an easy way to support your general health while you explore any fertility concerns with your healthcare team.
If your fertility journey has led you to consider donor eggs, we’re here to help you understand your options and what your next steps could look like. Contact us to learn more.
