Except for differences in size (because women tend to be shorter than men), women's frames are no different than men's frames, really.
Although "step-through" frames have typically been marketed as women's frames in the USA, they're ridden by both men and women elsewhere. This type of frame is very convenient for utility and commuter bikes in urban areas where one may want to mount/dismount without swinging a leg over the back of the bike.
The stepIn other words, the step-through is not really a women's frame. It is just a commuter/city-throughbike design that is not as sporty looking as a proper diamond frame, but if you're wearing regular trousers or a skirt they're easier to deal with.