Catholic doctrine says it's a sin to masturbate. Your seed needs to be deposited in the woman, not down the bathroom pipe. But everybody masturbates (male and female, Catholic, Muslims, buddhists, etc), and those who say they don't are lying. I once went for confession (a rarity for me). I confessed the usual things - being fast to anger, impatient with spouse......and I added in a wild card....And Father I also masturbated a few times. My penance were for the first two "sins", nothing was mentioned about the third "sin". I surmised the priest was also masturbating.