Sexual scents, long thought unimportant in human sexuality, in fact convey information to women about a man's genetic quality. Some women use sex to get along. Return to Table of Contents. Yes, women have sex to get what they Female motives for sex they're not always timid about it. Many of those complexities, say the authors, can be explained by human evolution: So she decides she will go home with her friend—to show him how it's done.