When a women has an orgasm the vaginal barrel resembles a vase, and the opening of the cervix dips down and sucks up sperm from the pool of the vaginal barrel thereby increasing the likelyhood of her getting pregnant and also it causes a man to ejaculate more intensely which releases two brain neuro-chemicals (natural opiates) called oxytocin and vassopressin which bonds the man to the offspring.
Through mans own arrogance and ignorance, fear, jealousy and envy he "avoids" this free ultimate pleasure that only the enlightened and exalted are able to achieve.