Women do it less because they are motivated/aroused by touch more than imagery (as in, a light touch or a sensual kiss will be a turn-on, not the sight or thought of a male penis). A teenage boy need only think of something arousing or see a cute girl and he'll sit uncomfortably in study hall until it passes. Luckily for men, as they get older, this is easier to control-- but the "urge" or "feeling" from said imagery remains (hence, why men masturbate more often... it doesn't take much to get a healthy man going).
(laughs) Please cite your sources.
Here you go. Is APA Format okay?
"Danoz," Daniel (2009). School of hard knocks & personal experience/observation. Washington, D.C.: TrekBBS.com Forums: Miscellaneous: Thread: "Masterbation" originally posted by "Master of Tarquin." http://trekbbs.com/newreply.php?do=newreply&p=2467436