Sex brings out a lot in people, which is usually a good thing. But if you’ve ever found yourself accidentally telling the girl you just met at the bar two hours ago that you love her, rest easy knowing science has found the reason behind your embarrassing blunder. According to a new study, men are biologically wired to want to spill their guts out to someone after sleeping with them—for a reason you’d never guess.

The study, which was published in the Personality and Psychology Bulletin, found that when men have sex, they’re subconsciously trying to keep their partner around so that she’s there in the future to take care of any possible children. Yup, the reason you told your Tinder match that you cried when your dog died in eleventh grade is because, biologically, you want to make sure she sticks around for the kids… and the kids’ dog.

The scientists in this study took a group of participants and exposed them to two separate kinds of stimuli: one sexual (think hot movie sex scenes) and one neutral. Then, they were asked to share an embarrassing story face-to-face with another participant. Those who had watched the sexy stimuli disclosed stories that were more personal in nature, leaving researchers to conclude that even thinking about sex leaves you more likely to spill gushy, emotional thoughts.

“The findings indicate that activation of the sexual system encourages self-disclosure, a strategy that allows people to become closer to a potential partner,” the authors explained. “Self-disclosure, in turn, further increases the desire for this partner and fosters relationship development.”

There you have it—whether you mean to or not, this is probably why you end up telling your adult sleepover companions your deepest, darkest secrets.

Photo: iStock/gpointstudio