The Pill Makes Women Pick Bad Mates | LiveScience

This link is from LiveScience, and discusses an article in Proceedings of the Royal Society B: Biological Sciences.



http://www.livescience.com/culture/080812-contraceptive-smell.html



The basic idea behind this study is that birth-control pills (BCP) cause a woman's body to be hormonally pregnant. That is, she is not releasing an egg and therefore has no need for a mate. This affects her ability to recognize a mate with differing MHC molecules. MHC molecules are part of our immune response. Diverse MHC molecules allow one to recognize more foreign invaders.



So for your (future) offspring, it is best if you mate with someone who does not share your MHC molecules. So how do you tell? Run a genetic screen on everyone you date? Nah, turns out you can smell 'em. You just don't realize. The article brings up some really interesting possible consequences of not recognizing them because of the interference of BCP.



See also this article:

http://www.livescience.com/health/070207_romance_gene.html



It goes into more detail about the whole MHC link to mate selection.