Posts Tagged ‘pill’

Women on the Pill Choose Wrong Sex Partners

September 26, 2008
The criteria that identifies a right sex partner, according to biology, (obviously I don’t have my say in this), is that he/she has the most different genetic makeup.

Quickie on genetics: 
Having two genetically different parents increases the chance for healthy offspring: for each gene, a zygote (formed when a spermatozoid reaches the ovula) receives a copy from his mom, and one from his dad. If both copies carry the same mutation (homozygotes) recessive diseases will express. So the parents might have been only carriers, but the baby will be affected by the disease. Whereas if the mom is a carrier but the dad isn’t, the baby is a heterozygote: he ends up only being a carrier.

But birth control pill makes women desire the wrong men… according to a recent U.K study published in Proceedings of the Royal Society B: Biological Sciences. “If this really happens in the real world, women on the pill would end up choosing a more genetically similar mate than she would otherwise choose and
the implications go on from there,” study researcher S. Craig Roberts, PhD

In an earlier U.S. study, women who were genetically similar to their partners reported being less satisfied in their
sexual relationship with their partner — and were seeking more new sex partners — than were women with genetically dissimilar partners.

Animal studies show that female mammals can smell out males whose MHC genes are different from their own. MHC genes affect important immune responses. By mating with males who have different MHC genes, females give their offspring a better disease-fighting repertoire.Rachel Herz, PhD, author of The Scent of Desire and a faculty member at Brown University, says there is a real connection between body odor, MHC, and the mates a woman chooses. Hence the T-shirt-sniffing studies. Herz and her team paid 37 women to smell men’s T-shirts before and after going on the pill. Then they compared the women’s before- and after-pill ratings of the odors to the control group 60 women not on the pill. The result: After taking the pill, women shifted toward preferring genetically similar men. Women who did not take the pill slightly increased their preference for genetically different men.

Possible explanation?           
In animals, when females become pregnant, they start to prefer scent of males with similar genetics. This may allow them to seek out males that will help them protect and raise the baby. And since the Pill makes your body think it’s pregnant (with progesterone, which is secreted by the amniotic sac in pregnant women), it would have the same effect.    

what i have to add:
I went off the pill twice in the last 4 years. The first time, my (male) ex and I broke up and I ended up with a girl. As far as I know, my ex and I had the most dissimilar genetics you could find. The second time… after a whisky dick and a totally EDed partner… well I haven’t had sex in a month.

Then again, an important assumption in the study is that odours play a strong role in partner choice… more than performance? I ask. No, I answer.
That’s why even off the Pill, I’m still attracted to those who made me want to start taking the Pill. What are your experiences? do you think odour is determinant to that point?

Finally, let’s just say that whatever the Pill does or doesn’t do to our tastes, without it, I couldn’t have had the luxury to marvel at all genetic variety, let alone sample it.

found this on a may 2007 post by blogger. On May 9, 1960 – the FDA (Food and Drug Administration, US)approved the first birth control pill.