According to Body Sense magazine, everyone emits aromatic molecules that indicate genetic compatibility with another person. I find this really interesting! As it turns out, this genetic signature, called major histocompatibility complex (MHC), can be interfered with by contraception pills. Generally, researchers find that the best partners have different MHC odors. Couples of dissimilar MHC genes have been found to remain more faithful to each other and report being more satisfied in their relationship. Women on the pill, however, tend to be attracted to mates with identical MHC odors. In short, women may prefer different men when they're on the pill than when they're off it. Crazy!
