The Intriguing Science of Sleepiness After Sex

Picture this: after an intimate session with your partner, you’re ready for some pillow talk or perhaps a shared laugh. But instead, your partner starts snoring next to you. Sound familiar? We’re here to explore a widely experienced yet often misunderstood phenomenon: why do people, particularly men, feel so sleepy after sex?

The Biological Symphony Behind the Snooze

Let’s start by getting one thing straight. This post-sex sleepiness isn’t about boredom or a lack of interest, far from it. It’s all down to biology. The human body is a wonderful and complex machine, especially when it comes to our hormones.

When you experience an orgasm, your body releases a cocktail of hormones, including oxytocin, prolactin, gamma-aminobutyric acid (let’s stick with GABA for simplicity), and endorphins. Each of these contributes to that fuzzy feeling of relaxation and sleepiness you might feel.

Oxytocin, often called the ‘love hormone,’ is particularly interesting. This hormone is associated with reducing stress and defensiveness, fostering a sense of calm and fearlessness. Sounds perfect for a peaceful slumber, doesn’t it?

Prolactin: The Sleepy Sentry

Prolactin also plays a starring role in this narrative. It not only contributes to sleepiness but also decreases arousal after sex. People with higher prolactin levels often experience increased daytime sleepiness. This intriguing link between prolactin and drowsiness helps explain why we might feel so inclined to nap post-sex.

Interestingly, one study found that prolactin levels were 400% higher after intercourse compared to masturbation, indicating that sex might be more physiologically satisfying. Initially, prolactin was thought to be responsible for why men can’t immediately go for “round 2,” but recent research has challenged this idea. The plot thickens!

Evolutionary Whodunit: The Purpose Behind Post-Coital Sleep

As for why feeling sleepy after sex is advantageous from an evolutionary perspective, we’re still exploring the possibilities. One idea is that the hormonal cocktail released post-orgasm promotes partner bonding. The sleepy sensation might simply be a side effect of these hormones.

Others propose a slightly more controversial theory. They suggest that post-coital sleepiness could be a mechanism to prevent partners, particularly women, from seeking out additional mates. Given that finding another partner is much more challenging when you’re asleep, it’s an interesting thought. However, these theories require further research before we can fully understand the evolutionary benefits.

Why Men? Unmasking the Sleepy Stereotype

So, why is the stereotype more associated with men dozing off post-coitus rather than both genders? The answer might lie in the notorious ‘orgasm gap.’ If you’re wondering what that is, it refers to the differing frequency of orgasms experienced by men and women during sexual activity, with men reportedly climaxing more often. As orgasms trigger the release of these sleep-inducing hormones, it might explain why men are often the sleepier party post-sex.

However, it’s essential to remember that feeling sleepy after sex isn’t gender-specific. Studies have found that women can feel just as sleepy as men after sex, particularly after orgasm.

Embracing the Snooze: It’s Only Natural

In conclusion, if you or your partner feel like catching some Z’s after a session between the sheets, don’t worry. It’s not a reflection of their interest or your performance, but rather a testament to the complex and fascinating cocktail of hormones at play.

It’s a natural, physiological response that happens to many of us, and perhaps understanding the science behind it can make it a topic of shared amusement rather than frustration. After all, there’s a kind of intimacy in sharing that post-coital snooze, don’t you think?


This article provides information based on scientific research and is not intended to be a substitute for professional medical or psychological advice. Always seek the advice of a qualified healthcare provider with any questions you may have regarding a medical or mental health condition.

Further reading

Kruger, T. H., Haake, P., Chereath, D., Knapp, W., Janssen, O. E., Exton, M. S., Schedlowski, M., & Hartmann, U. (2003). Specificity of the neuroendocrine response to orgasm during sexual arousal in men. Journal of Endocrinology, 177(1), 57-64. Link

Snowdon, C. T., & Ziegler, T. E. (2015). Variation in prolactin is related to variation in sexual behavior and contact affiliation. PloS one10(3), e0120650.