Romantic Chemistry Sticker

Women have the amazing capacity to, through their sense of smell, sniff out and prefer men with a dissimilar major histocompatibility complex, that is, men with genes dissimilar to their own. The biological reason for this preference is simple: The more dissimilar the genes, the less chance there is of inbreeding, and thus the healthier the children potentially produced by a man and a woman. It is in part our natural preference for a dissimilar major histocompatibility complex that normally prevents us from being attracted to members of our family. However, according to a 2008 study published in The Proceedings of the Royal Society B: Biological Sciences, women using oral contraceptives show the opposite tendency. They prefer men with a genetic makeup similar to their own. Their romantic chemistry has been altered. The problem with this is the same — once women stops using hormonal contraception, they may find their chosen partner less desirable.