New study busts myth behind why men must wait for round two of sex

Researchers are now closer to finding out why men can’t go straight into round two following orgasm after a new study ruled out a common excuse for it.

No matter how up for it they might be, all men need a break before resuming sexual activity after they ejaculate. Average times vary from just 15 minutes for an 18-year-old or up to 20 hours for a 70-year-old man. It was long believed the reason for a man’s refractory period after sex was due to the hormone prolactin.

It had long been assumed the hormone prolactin controlled how quickly men could resume sexual activity after orgasming. A 2013 study suggested high levels of prolactin in men were linked to a lower sex drive and erectile dysfunction. It still isn’t fully known what impact that prolactin has on men but it is thought to affect their sexual function and arousal.

Now a new Portuguese study published this week has revealed prolactin levels have no impact on a man’s readiness to go again, the Daily Mail reports. In the research, conducted by the Champalimaud Centre for the Unknown, scientists changed mice’s prolactin levels, expecting to see the time between when they could have sex again change.

Dr Lima said that as prolactin had a “central role” in “suppressing male sexual behaviour” it was then assumed the hormone controlled when men for go for round two. “However, a direct link between prolactin and the male post-ejaculatory refractory period was never directly demonstrated. Still, this theory has become so widespread that it now appears in textbooks as well as in the popular press,” she told science journal Nature, according to the Daily Mail.

Ruling out prolactin as the reason behind men’s refractory periods after sex meant scientists could now test other theories instead.

“Now we can move on and try to find out what’s really happening,” Dr Lima said.