Semen Is An Antidepressant say Psychology Today
In this study that no doubt could have seen many different results due to the many uncontrollable factors. Still the study and article was fun reading.
This study controlled for relationship duration, amount of sex, use of the Pill, and days since last sexual encounter.) So it appears quite possible that the antidepressants in semen might have a real mood-elevating effect.
Finally, recall that in addition to antidepressant compounds, semen also contains two female sex hormones, follicle-stimulating hormone (FSH) and luteinizing hormone (LH). FSH spurs egg maturation in ovary. LH is involved in triggering ovulation. Why would semen contain compounds that encourage ovulation? From an evolutionary perspective, this makes perfect sense.