Guest over a year ago I did too many times and yesterday I ejaculated blood with sperm, I don't think it is healthy to do it, I am still trying to figure out what is happening. Black bug like in my sperm?
hold sperm inside is harmfull - Sexuality & Relationships - MedHelp
This will prevent you from ejaculating and you can continue with your lovemaking for as long as you want by just contracting these muscles and delaying ejaculation.
“Injaculation”: Is It Dangerous For Guys To Prevent Ejaculation During Orgasm? — Sex And Psychology
I can't remember the right terms, but there's something, a muscle or something of that sort, that prevents your semen from backtracking into your bladder. I believe you actually mean that you are preventing yourself from ejaculating semen the fluid that carries sperm.
I used to be very concerned about this practice, but I haven't worried about it for a long time. So, you take a longer time to reach an orgasm and finally ejaculate again.
For instance, consider this finding from a study of multiply orgasmic men 1: