Surprised that you're feeling down after getting it on? This video from Stuff Mom Never Told You explains exactly what's going on with our bodies when we're suddenly not so happy after sex. Post-coital sadness can last anywhere from five minutes to two hours, and it's more common than you think—one recent study found it affects nearly half of women at some point. Postcoital Dysphoria: Prevalence and Psychological Correlates. Schweitzer RD, O'Brien J, Burri A. Sexual medicine, 2015, Oct.;3(4):2050-1161.

For most of us, we can blame the blues on chemicals. Our brain releases lots of dopamine when we orgasm, but then comes prolactin, a chemical that regulates dopamine levels to stop us from becoming too unfocused and unproductive. During sex, there's less activity in our prefrontal cortex (where serious thinking goes on) and our amygdala (where fear and anxiety comes from), but afterward they get back to work. All this leveling out can make us feel sad right after we felt amazing. On a more serious note, post-coital sadness has also been linked to past sexual abuse, so if it's something you experience regularly, it's worth bringing up to a doctor or therapist.

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