There’s a ton of research on sex out there, yet not much beyond the climax. But a recent study sheds some light on what happens behind closed doors— after the deed is done. This study is one of the first on emotional bonding after intercourse. Scientists say it’s important to study post-sex behavior because reproductive strategies may influence how we act before, during, and after the act of sex. Specifically, falling asleep after sex may prevent any kind of commitment conversation.

Researchers asked 456 participants in their early twenties about their experiences with their partners after sex. People whose partners rolled over and started snoozing immediately after sex had stronger desires to cuddle and talk (which we’re guessing is pretty hard to do if the other person’s asleep…). Scientists suggest falling asleep after sex may be a non-conscious attempt to forgo a bedside chat, which may hinder relationship bonding. And contrary to what researchers predicted, men weren’t more likely to fall asleep first (although researchers admit participants’ accounts of who falls asleep first might not have been so accurate). But before trying to stay wide-eyed in bed, note that participants were 20 year-old undergraduates, which has led to some skepticism regarding the study's results. (Are college students really post-coital wisemen?) And scientists are still unsure whether falling asleep after sex is psychological or physiological.

Studies have yet to find solid evidence that orgasms can have a hypnotic effect, although in some cases, orgasms can increase prolactin levels, which are linked to sleepiness. (Oh oh it’s magic, you know!) Prolactin secretion and sleep. Spiegel, K., Follenius, M., Simon, C., et al. Laboratoire de Physiologie et de Psychologie Environnementales, Strasbourg, France. Sleep, 1994 Feb;17(1):20-7. Specificity of the neuroendocrine response to orgasm during sexual arousal in men. Kruger, T.H., Haake, P., Chereath, D., et al. Department of Medical Psychology, University of Essen, Federal Republic of Germany. Journal of Endocrinology, 2003 Apr;177(1):57-64).. But whether falling right asleep or taking some time to cuddle, don’t forget to stay safe while you’re at it.