Because women are built with wider hips than men, they are much more flexible in the hip area. Their hips turn easily and naturally on the back swing. A hip-width stance allows for a more dramatic weight shift back and away from the ball. Women also have a lower center of gravity, which is useful to generate the power in their swings.
A good golf swing must start with a solid foundation. Some feel women need to widen their stances to be successful. Women actually look more comfortable and better balanced with wider, hip-width stances.