Religion is an emotional institution.
That being said, men despite some beliefs are subject to emotion and women can be very rational. But in general I hope I am not putting my foot in my mouth here, but hopefully we can say that women generally speaking are more emotional than men. For instance, with me and my wife, she gets extremely emotional whenever she thinks about here deceased grandfather and father, and relates this single issue to the strength of her faith. She has to believe she can see them again. I don't consider myself devoid of emotion, but tend to desire to separate emotion from rationality. And not to say I have always been this way, but it can be learned.
Religion and JW's especially exploit EMOTION. Fear, anger, sadness. Sit down at any meeting and the talk starts off with how bad life is and how miserable we all are, plays on our sadness over loss, disappointment with "bad" people, uses guilt to control. At its core its emotion driven, not reason like JW's think they are. I even used to tell people when defending my faith, that witnesses are different because its rational, how freaking embarrassing I ever said such a thing.
So I guess what I am getting at is there may (i don't know one way or the other), may be more men, simply for the emotional nature of religion.