Contraceptive pill influences partner choice

Aug 13, 2008

The contraceptive pill may disrupt women's natural ability to choose a partner genetically dissimilar to themselves, research at the University of Liverpool has found.

Disturbing a woman's instinctive attraction to genetically different men could result in difficulties when trying to conceive, an increased risk of miscarriage and long intervals between pregnancies. Passing on a lack of diverse genes to a child could also weaken their immune system.

Humans choose partners through their body odour and tend to be attracted to those with a dissimilar genetic make-up to themselves, maintaining genetic diversity. Genes in the Major Histocompatibility Complex (MHC), which helps build the proteins involved in the body's immune response, also play a prominent role in odour through interaction with skin bacteria. In this way these genes also help determine which individuals find us attractive.

The research team analysed how the contraceptive pill affects odour preferences. One hundred women were asked to indicate their preferences on six male body odour samples, drawn from 97 volunteer samples, before and after initiating contraceptive pill use.

Craig Roberts, a Lecturer in Evolutionary Psychology who carried out the work in collaboration with the University of Newcastle, said: "The results showed that the preferences of women who began using the contraceptive pill shifted towards men with genetically similar odours.

"Not only could MHC-similarity in couples lead to fertility problems but it could ultimately lead to the breakdown of relationships when women stop using the contraceptive pill, as odour perception plays a significant role in maintaining attraction to partners."

Source: University of Liverpool

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Dologan
not rated yet Aug 13, 2008
Interesting finding, no doubt, but I can't but question the real-world relevance of a result as restricted in scope as this. The complexity of human mating interactions can hardly be reduced to smells alone and to draw any conclusions based on such oversimplification is just premature. How about they back that up with some sociological study of the pills influence on match-ups and break-ups for some sound statistical foundation rather than speculation?
marjon
not rated yet Aug 13, 2008
I think more research should be conducted into human pheromones and mating. How dependent is the male libido on female pheromones? Do all male schools help the boys focus on school, not girls? Only in the past few decades have young men been exposed to so many young women.
Reminds of how crazy dairy bulls get when separated from their cows in heat.
superhuman
1 / 5 (1) Aug 13, 2008
Opposite sex pheromones are like hard drugs, proper ones will hook you up in no time if you keep breathing them, then they proceed to mentally incapacitate you - Biohazard Level 4!
mrlewish
not rated yet Aug 13, 2008
Your missing the point. The point is that if a large group of the population picks the "wrong mate" autoimmune disorders will become more common in the general population. ie. The apparent increasing prevalence of certain conditions such as autism might be a result of the law of unintended consequences. This can be checked by looking at the MHC of couples with autistic children compared to those in the general population.
Roj
2 / 5 (1) Aug 14, 2008
This abstract skips supporting references to 1) mid 1990 studies that established a switching of women's sniff preference during their 3-day ovulation window, and 2) correlation of T-cell diversity to men's shirts discerned by scent.

There was about 5 years of supporting peer review. If this physiological process is one valid mechanism for a women's choice, any suppression of ovulation would be suspect for masking it.

The concept of birth control hormones affecting this scent process should not be surprising if the prior studies are properly referenced.