Highlights
- Research shows that people have a tendency to fall asleep after sex, especially if it includes orgasm.
- A hormonal cocktail released during lovemaking may be behind our post-sex behaviors.
- People with a strong desire to cuddle after intercourse may need it as reassurance of the partner’s commitment.
- Evolutionary psychologists think men stay awake after sex as a form of “mate-guarding” behavior.
We’ve all heard a joke or two about a man falling asleep the second he’s had an orgasm. But why do some people need to sleep after sex, while others like to cuddle and chat? Differences in post-sex behavior may have evolutionary as well as psychological causes.
Why Do Some People Fall Asleep After Sex?
A theory that sex is a natural sleeping pill isn’t just an urban myth. A Norwegian study of over a thousand people revealed that sexual activity, especially when it ends in orgasm, sends both men and women to the land of snooze.
There are several physical explanations on why people sleep after sex. Let’s explore.
Sex Usually Happens Late in the Day
In Western societies, it’s common for people to get frisky in the evening or at night. Date and dinner or a quick hookup — everything seems more sensual after dark. Hard to imagine an erotic get-together in candlelight when it’s lunchtime!
Since we’re having most sex around bedtime, it’s only natural to drift off after pleasure. On top of that, doing it in the dark or in a dimly-lit room supports the production of melatonin, the sleep hormone.
Sexual Activity Makes You Tired
For most people sexual activity is like moderate exercise. According to a study, conducted on young people, men can burn approximately 100 calories per session. The active partner gets a better workout, and in heterosexual couples it’s the guys who usually do the heavy lifting (or thrusting). Add to that the orgasmic release, and that explains why men like to nod off after a hot coupling.
Sex Releases Relaxation Hormones
Intercourse may feel like an out-of-this-world experience but it’s also a physiological process. A powerful cocktail of substances gets released when we become aroused, touch another person, and climax.
Oxytocin, the bonding hormone, is known to promote relaxation. The body produces the hormone prolactin in large amounts after an orgasm, especially when it happens as part of intercourse. This substance creates a sense of sexual satiety, plus it can literally make you sleepy.
If both men and women produce those “chill out and get some rest” hormones, why is it the man who often dozes off first? Could it be because in heterosexual couples it’s the men who can orgasm consistently from intercourse while many women don’t? Now, there’s something to think about (and work on)!

Some Prefer Cuddling After Sex
Sleep may be the body’s natural reaction, but some people prefer other types of post-sex behavior, such as cuddling. In a study published in the Journal of Social, Evolutionary, and Cultural Psychology, researchers tried to understand Post-coital time interval (PCTI) by studying the behaviors and attitudes of couples toward time spent together after sex.
As it turned out, the need for bonding and cuddling after climax was especially strong among the participants whose partner had a tendency to fall asleep right after. There was also a link to a person’s attachment style — women who showed anxious tendencies needed more of their partner’s reassurance.
Controversial Evolutionary Theories
Evolutionary psychology is a scientific discipline aiming to explain human behavior through an evolutionary lens. In that context, our sexual behaviors mostly serve a reproductive function, even if these days people use birth control and make love for fun.
This theory offers some hypotheses as to why people behave the way they do after intercourse. For example, falling asleep after orgasm may be a subconscious way to avoid commitment-related conversations.
Another evolutionary theory is mate guarding. Animals do it to make sure their genes are passed on and that the mate will be able to produce offspring. In humans, this tendency may show up in men who stay awake after sex and in women’s preference to sleep together after intimacy.
One evolutionary study of heterosexual couples reached a surprising conclusion — it was the women, not the men, who fell asleep more often after vaginal intercourse. Scientists have a theory that semen contains substances which promote sleepiness. This is thought to be nature’s way of making sure the female remains reclined after sex, which prevents the semen from leaking and increases the odds of pregnancy.
Of course this trick won’t work for couples who use condoms as protection but Mother Nature hasn’t caught up on that (yet?).
We should note here that evolutionary theory is not an exact science — in fact, it’s somewhat controversial. Some feel that it oversimplifies complex human behaviors and reinforces gender stereotypes. You’ll have to judge for yourself if these theories make sense to you.

When You Have Mismatched Post-Sex Behaviors
If you and your partner have different behaviors after intercourse, this could lead to conflicts. Even if the sex is great but one you is regularly left alone and wide awake while the other happily snores, you should talk about it.
Here are some tips on managing mismatched postcoital behavior:
- Make love during the day. Experiment with morning or lunchtime sex and see if it makes a difference. Doing it in daylight will help you stay awake. Plus, you get a better view of your lover’s body!
- Get some rest before sex. Taking a nap before a romantic evening is not always an option, but with a bit of planning, you can make it happen. This will increase your odds of staying awake after an orgasm.
- Add cuddling to foreplay. He or she loves to hug and kiss after the act, but you can barely keep your eyes open? Agree to add more touching and bonding to your pre-sex rituals.
- Show your affection. If your partner complains that you always doze off after making love, don’t take it lightly. This may be her or his way of asking for more signs of attention and emotional connection. Try to show signs of love and commitment more often.
When You Need a Little Help in the Bedroom
Navigating intimacy and relationships can get complicated if you have sexual challenges, such as erectile dysfunction. Thankfully, this condition is easy to manage with medication, such as Viagra, Cialis, or Levitra.
eDrugstore is here to save you the stress of making doctor’s appointments. With our free, telemedical consultation, a licensed physician can issue a prescription within a few minutes — at no additional charge. Learn more and order your medication here.

Anka Grzywacz is a sexologist, reproductive health expert and Certified Sex Coach™. In her online practice she helps busy women and couples solve their intimate problems.