is that your medical opinion? Because I've been fcuking for more than 20 years and this hasn't happened even once. Of course perhaps my partner and I have better than average control over our anal sphincters. Maybe you should change your diet?
As for me, I work with little old people who really can't control their sphincters, and they let 'em rip all day long. I'm not interested in being reminded of them when I'm having sex.
But hey, if you don't mind, more power to you.