Love May Be Blind, but It Sure Can Smell

The introduction of birth control pills in the early 1960s has been widely accepted as the chief culprit for the sharply rising divorce rates which followed (from 9.6 per 1000 marriages in 1963 to 19.4 per 1000 marriages ten years later), as fewer women were forced to “think of the children” and remain locked in unhappy marriages. As it turns out, we may have been barking in the right forest but up the wrong tree. While the pill certainly freed women from having to live with unwise choices in long-term mates, it may also be responsible for their having made those unwise choices in the first place.

Let’s revisit the Stinky T-Shirt Study, which showed that women are biologically programmed to sniff out mates with vastly different genetic makeup from their own, with one interesting exception: Women using oral contraceptives prefer the scent of men with major histocompatability complex (MHC) profiles very similar to their own. As the pill mimics pregnancy in women, and pregnancy is a vulnerable state, it appears to foster a preference for genetically similar kin, as these are likely to be seen as protectors.

“It is like choosing a cousin as a marriage partner,” says Rachel Herz, author of The Scent of Desire. “It constitutes a biological error.” In short, if you are looking for a man to be the father of your child, go off the pill before you start your search, or you might find yourself, years later, wondering what you ever smelled in that guy.

“Interestingly,” says Herz, “one of the most common things women tell marriage counsellors is ‘I can’t stand his smell’.”