The post-coital glow.

According to a new study, that after-sex "glow" can last for up to 48 hours, yes that's right, a full TWO days afterwards. Previous research has established that getting up close and personal with your significant other releases oxytocin, often referred to as the hormone of love, but we never really knew how long this effect lasted. This study, conducted by Psychological Science, (a journal of the Association for Psychological Science), asked 214 couples to keep 'sex diaries' for two weeks using "a 7-point scale, where 1 = not at all, 7 = extremely". This included information on how often they had sex, how happy they were with said sex and how satisfied they were with their relationships. The results showed that said 'glow' lasted for two days after the main event but faded by day three. The lead author of this study Dr Andrea Meltzer, of Florida State University, elaborated on the results:

"This is the first research to quantify the length of the sexual afterglow and to examine its benefits. "Our research shows that sexual satisfaction remains elevated 48 hours after sex.  The afterglow appears to last approximately the same length of time that it takes for peak sperm concentration to be restored "And people with a stronger sexual afterglow — that is, people who report a higher level of sexual satisfaction 48 hours after sex — report higher levels of relationship satisfaction several months later".

This did not differ according to the research participants age or gender with Dr Andrea and her colleagues concluding that this provided "robust evidence" for afterglow 48 hours after sex.