This study of non-condom using couples has been around the Internet for a while. The women scored lower on pencil and paper test for depression than similar coeds in copulating couples who always used condoms. That is, they felt Better.
They didn't study female partners who did CIM with swallow. One news story quoted a study researcher as saying that the psychoactive molecules in semen were similar to those in hormone pills like birth control pills that survive transit through the aggressively acidic environment of the stomach so maybe similar molecules in swallowed semen could reach the the gut intact where they might be absorbed. The obvious problem with that is that pharma hormones are in pills designed to pass through the stomach unscathed. Obviously more research is needed. I believe that is what the researcher said too
I try to see only ladies who do CIM with swallow because it feels good emotionally to have my partner, even if only for the two hours, incorporate a tiny bit of myself into her self. One of my ladies says BBBJ NQNS is the closest thing to "real" sex in the age of the condom and I quite agree. I've learned to read the code in the P411 "Activities" lists: BBBJCIM with Pearl Necklace but without BBBJ NQNS means "she doesn't" Pity.
An obvious question that most ladies will probably be reluctant to tackle is:
If you swallow and circumstance provide an interval where you don't get to/don't have to swallow for a while, say a week or so, do you Feel different? Worse?