I'd say the okc stats reveal a general trend that does indeed exist.
Women are taking a much bigger risk by sleeping with a man, it should count. My risk of catching diseases or really having any consequences at all for sleeping with a woman who is legally of age are almost nill if I can manage to avoid her. For a woman though, for most of history she could catch a disease or get pregnant which is a lot easier if you have a guy around to help out even if you have a community, if you are by yourself entirely there is a good chance you won't survive and a even greater chance your pregnancy will be complicated. This is why our society provides so much welfare to single mothers...community support in lieu of having a guy around.
Also there is the social factor, my friends laugh at me if I fuck an ugly fat girl. Women can't wait to call each other sluts which seems to mean a lot. This is another way your typical sluthater is like a woman... hardly any men I have ever met have ever bothered to call a woman a slut or shame her for promiscuity.