Okay, so it's a stereotype, but it made me laugh.

More content stolen from rec.humor.funny:

A study in Wisconsin showed that the kind of male face a woman finds attractive can differ depending on where a woman is in her menstrual cycle.

For instance, if she is ovulating, she is likely to be attracted to men with more rugged and masculine features.

If she is menstruating, she is likely to be impressed by a man with scissors through his temple and a bat shoved up his ass.