Orgasms are believed to be one of the best sensations you can feel. Yet, after such a "high," you begin to feel "down," overcome with sadness, anxiety, and even crying spells. Now, researchers at Queensland University of Technology in Australia suggest the post-sex blues affect men just as much as women, even if the sex was good.

“Everyone assumes what happens in the bedroom is normal but there are a wide range of responses in the period of time immediately following consensual sexual activity, known as the resolution phase,” said Robert Schweitzer, study author and a professor at QUT, in a statement.

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These behaviors range from wanting to cuddle to being alone to feelings of sadness, known as post-coital dysphoria (PCD), or postcoital tristeess, which literally translates to "sadness" in French. These emotions can last between five minutes and two hours, with possible tears. Previous research has found about half of women report experiencing PCD symptoms at least once in their lifetime with five percent going it a few times within the past four weeks.

Schweitzer notes this phenomenon is not just limited to women — men experience the bedroom blues too.

"There is anecdotal evidence that postcoital dysphoria is not uncommon in both men and women," he said.

However, researchers have yet to find conclusive evidence about what causes PCD.

April Masini, relationship expert and author, believes post-sex blues could be the result of a realization that the relationship may not be going anywhere beyond the bedroom.

"Many times people (usually women) try to leverage sex into love. They get caught up in the whirlwind and in the morning, realize there’s no 'I love you,' or 'I have to see you tonight,' uttered," she told Medical Daily.

Meanwhile, Nicole Prause, sexual psychophysiologist and neuroscientist, believes a lack of an orgasm or testosterone levels can make these negative emotions come to the surface.

"Communication after sex is often negative," she told Medical Daily.

A 2016 study in the Journal of Social and Personal Relationships adds evidence to this claim. Researchers found when testosterone levels were high, post-sex communication was less intentional and less positive. Those who had high testosterone levels, but did orgasm, did not experience negative post-sex communication. Typically, lower testosterone is linked with greater and more positive communication after sex. It's believed the "negative feedback" may be out of physical frustration of not achieving orgasm.

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The causes for PCD are still speculative, but Schweitzer has hinted it could be tied to a "loss of self."

"There may be a group of people who find that this “loss of self” sets off a response of dysphoria [a general state of unease], particularly when the individual feels a vulnerable sense of self, which may result from a number of developmental issues," he previously told WBUR, Boston's NPR News Station.

Schweitzer and his colleagues now seek to survey both men and women on post-sex blues to develop a scale that will allow them to assess the resolution phase — the phase after sex. He believes this will help them determine whether the sex was strictly about excitement and pleasure.

"This study will also gather data on the frequency of different experiences and whether they relate to other factors," he said.

Until then, Masini cautions to be careful not to misread your partner's actions during the resolution phase. Not everyone likes to cuddle or show affection after sex.

"Sometimes, a partner will be thinking about marrying you, but you misread this because you’re assuming that the absence of affection after the act means an absence of feelings for the relationship," she said.

It's best to get to know your partner, and see what their post-sex style is, and whether they like to be affectionate, and connect socially and emotionally after sex. These behaviors can either reveal everything, or nothing about the relationship. Therefore, it's important to not misinterpret.

To take part in Schweitzer's study, click here.

QUT Institute of Health and Biomedical Innovation. 2017. “Snuggle, run or cry: What’s your ‘normal’ after sex?” News Release.

See Also:

Why Some People Make Loud Noises Even Before Orgasm

Why Do I Fantasize About Other People During Sex?