Men experience Postcoital Dysphoria (a wave of negative emotions after sex) at rates comparable to women, according to new research from Queensland University of Technology (QUT).
Postcoital Dysphoria (PCD) is a condition characterised by a short-term period of counter-intuitive responses after consensual sex, involving inexplicable feelings of irritability, sadness, anxiety, or tearfulness.
Studies of PCD in women have shown that up to 46.2% of women have experienced PCD in their lifetime.
In one female study the feeling of PCD was described as "feeling hollow", "homesickness", or a "yearning for something that was missing".
However before the QUT study no prevalence studies for men had been conducted. The researchers state in the paper that PCD in men may not have been studied a great deal so far because it contradicts "dominant cultural assumptions about the male experience [of] sexual activity and of the resolution phase".
Professor Robert Schweitzer, a psychology researcher from QUT, who co-authored the paper with masters student Joel Maczkowiack, told BuzzFeed News that men may have been relatively ignored in the PCD literature because of societal expectations.
"My guess is that we have such a cultural view of what sex is for men that the very idea of men having experiences which are aversive are just not even considered," said professor Robert Schweitzer, a psychology researcher from QUT, who co-authored the paper with masters student Joel Maczkowiack.
The QUT study involved an international online survey of over 1,200 men and found that 41% of men reported experiencing PCD in their lifetime. The study also found that 3 to 4% of men experience PCD on a regular basis.
For these chronic sufferers of PCD, these adverse emotional reactions can significantly affect sexual enjoyment.
John*, a 41-year-old participant in the QUT study, told Schweitzer that he has suffered negative feelings such as emotional exhaustion and aggression after orgasm since his 20s.
John's PCD has led to a decrease in intercourse with his wife in the past few years.
"It is because I cannot bear negative feelings and emotions anymore," he said. "I am avoiding any sexual behaviour as much as possible, despite still feeling needs."
Humans experience four distinct phases in their sexual cycle, according to a landmark book in sex psychology published in 1966 called Human Sexual Response.
The book posited the EPOR theory of human sexual response cycle, which includes: Excitation, Plateau, Orgasm, and the Refractory period. This cycle is still widely accepted in the literature today as the frame of human sexual experiences.
The refractory period is the time that the body experiences resolution after an orgasm and returns to its normal state, with decreasing blood flow to the genitals (resulting in a loss of erection) and a general sense of wellbeing.
For men, this means that they cannot physically respond to further sexual stimulation (although women do not experience refractory periods in the same way and may simply experience orgasm fatigue).
The refractory period is thought to be important for bonding because couples who pillow talk, kiss, or cuddle during that time report higher relationship or sexual satisfaction.
PCD takes place during the refractory period and, while there are no definitive reasons for why it occurs, it has been related to hormone fluctuations during sex (such as rises and falls in dopamine and prolactin), says Schweitzer.
Some studies have even proposed the evolutionary benefits of PCD relating to securing long-term relationships for women and short-term relationships for men.
However, Schweitzer dismisses the claim that PCD is beneficial in evolutionary terms.
"From an evolutionary point of view, this is what makes it [PCD] so interesting, because it doesn't make any sense. Evolutionary theory would want to propagate any activity which is going to propagate the species rather than result in avoidance."
Instead, Schweitzer believes that PCD is the result of multiple factors of psychological experience, including how we emotionally attach to others.
Dr Miriam Forbes, a psychology and emotional health researcher from Macquarie University, believes that PCD is an experience that can also result from cultural pressures.
Forbes notes that people have a variety of responses to sex, "including the negative emotions about guilt and shame and disgust, which can come from ideas about sex".
"People are so complex, there are so many reasons why people might react in a different way after sex," she said.
Researchers have theorised in the past that this empty or irritable feeling in the post-orgasm phase could have an association with other causes of distress such as trauma, abuse, or depression.
In women, PCD has shown modest associations with childhood sexual abuse as well as general psychological distress, although the melancholy experienced during the refractory period has been found to be mostly unrelated to other forms of emotional distress in life because of its short-lived, inexplicable nature).
In the QUT study, psychological distress was found to be strongly associated with male experiences of PCD and childhood sexual abuse showed a small association.
However, Schweitzer doesn't believe that these results were statistically significant enough to comment on.
"It is very, very small in our sample ... it's really just a few percentage points," he said.
The authors also found suggestions that sexual dysfunction, such as erectile dysfunction and premature ejaculation, are related to PCD.
Forbes believes that PCD may be, at least in part, simply a reflection of an individual's broader emotional experience.
"I think in psychology, when we talk about emotional distress, these are the feelings that we're talking about, and these are the feelings being captured by Postcoital Dysphoria," she said.