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This year 2.25 million Americans will get married—and a million will get divorced. Could birth control be to blame for some of these breakups? Recent research suggests that the contraceptive pill—which prevents women from ovulating by fooling their body into believing it is pregnant—could affect which types of men women desire. Going on or off the pill during a relationship, therefore, may tempt a woman away from her man.
It’s all about scent. Hidden in a man’s smell are clues about his major histocompatibility complex (MHC) genes, which play an important role in immune system surveillance. Studies suggest that females prefer the scent of males whose MHC genes differ from their own, a preference that has probably evolved because it helps offspring survive: couples with different MHC genes are less likely to be related to each other than couples with similar genes are, and their children are born with more varied MHC profiles and thus more robust immune systems.
A study published in August in the Proceedings of the Royal Society B, however, suggests that women on the pill undergo a shift in preference toward men who share similar MHC genes. The female subjects were more likely to rate these genetically similar men’s scents (via a T-shirt the men had worn for two nights) as pleasant and desirable after they went on the pill as compared with before. Although no one knows why the pill affects attraction, some scientists believe that pregnancy—or in this case, the hormonal changes that mimic pregnancy—draws women toward nurturing relatives.
Women who start or stop taking the pill, then, may be in for some relationship problems. A study published last year in Psychological Science found that women paired with MHC-similar men are less sexually satisfied and more likely to cheat on their partners than women paired with MHC-dissimilar men. So a woman on the pill, for example, might be more likely to start dating a MHC-similar man, but he could ultimately leave her less sexually satisfied. Then if she goes off the pill during the relationship, the accompanying hormonal changes will draw her even more strongly toward more MHC-dissimilar men. These immune genes may have a “powerful effect in terms of how well relationships are cemented,” says University of Liverpool psychologist Craig Roberts, co-author of the August paper.
Note: This article was originally published with the title, "A Tough Pill to Swallow".
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23 Comments
Add Commentfirst, women too seek men for sex, and are frequently willing to provide financial support. The level of libido is of importance. A woman who has breast implants does this either for job advances or to attract more attention from men.
Reply | Report Abuse | Link to thisIn trials of inviting women for a casual date, then to trigger their sexual desire by physical touch, showed these women expressing amazement to find that this date with an undesirable man turned into attraction on a high enough level to consider having a crush. The crush in almost all cases leading to immediate desire for sexual consumption. This is just a small part of decades of trial and errors in relationship research. At present I have more than 50.000 words down including letters expressing love, sadness and demands from women who were part of the experiments.
Splendid, mind-boggling information. Thanks.
Reply | Report Abuse | Link to thisJust wish it had not been considered necessary to use the ridiculous word 'cheat' in this context. It makes relationships sound like a zero-sum game - often a self-fulfilling prophesy, unfortunately.
Hmmm. I am reading The Happiness Hypothesis, by Jonathan Haidt, which was not only published in 2006, but also conveys the same information as above. That is to say, I fail to see why this article (interesting as it was when first published) is still presented as news in December 2008!
Reply | Report Abuse | Link to thisIs it just me, or does it seem that this "study" is making huge assumptions? When a family or relationship decides to be on the pill, there are many things going on. For starters, it is the intent that this relationship (for whatever reason), is not ready to start a family and/or settle down. Somehow, I think all other considerations pale when compared to this.
Reply | Report Abuse | Link to thisYou seem to be mistaking anecdote for fact. Your concious mind is fooled into thinking it is "in control" of the situation, when in fact your primitive sub-brain actually does all the work, and provides information back to your concious mind that allows it to come to the conclusion it has already made. Lots of "thinking" is done this way, especially when it comes to sex. the "intent" of a relationship is moot. Its not even relevent. You should probably read about how such studies exclude the kind of variables you're talking about, so you'll understand why intent doesn't matter worth a lick.
Reply | Report Abuse | Link to thisAmen to that. Imagine if all of our social groups functioned the same way as a sexual relationship.
Reply | Report Abuse | Link to thisYou would have to pick one person in your family to love, only one friend to love, while shunning the rest because thats what we were taught to believe, life is a zero sum game.
Should life not be about finding and surrounding yourself with as much love as possible?
and dont mistake 'love' for 'lovin'
Reply | Report Abuse | Link to thisI would like to add something that could be inferred from this study and perhaps lead to another study.
Reply | Report Abuse | Link to thisIf you have similar MHC genes as you mate and produce an offspring they will have a less strong immune system. Thus leading in part to health crises facing children that we have in the US.
ildenizen: "...When a family or relationship decides to be on the pill, there are many things going on. For starters, it is the intent that this relationship (for whatever reason), is not ready to start a family and/or settle down. Somehow, I think all other considerations pale when compared to this...."
Reply | Report Abuse | Link to this---------------------------------------------------------------
Wow, this is some truly primitive thinking - should join the Taliban!
A "family" is created when two adults chose to marry. Kids, if any, become part of such already established family.
In developed countries, normal, intelligent families, generally practice some sort of birth control. The Pill is one common method.
Get it?
I think the big over arching idea people seem to be missing from the article is that the hormonal changes caused by Birth Control Pills (progesterone +/- estrogen aka hormones) causes psychological/emotional changes in those taking them. It's valid to think that altering normal hormones will have some kind of large scale effect on the brain/body whether it be physiological or psychological or some combination of both. It's really no different from the personality changes accompanying anabolic steroid use - "Roid rage".
Reply | Report Abuse | Link to thisNow to what extent this occurs is all up for interpretation.
But do consider large scale use of hormonal birth control seems to have started around the 1950s and become common place by the 1970s which correlates to the rise and peak of divorce rates in the US. Now granted there are probably a million social factors that can be attributed to the those rates the data is nonetheless interesting.
Haha agenthucky, I'm naturally a very monogamous (monoandrous?) woman, though I realize many women, and of course men, prefer multiple partners. I assume a variety of reproductive strategies helps ensure the survival of the species. You and I probably shouldn't date, however, as your polygamous strategy might then actually reduce your chances of survival ;).
Reply | Report Abuse | Link to thisAt any rate, I was on the pill when I met my former fiance. We hit it off and had good, if not mind-blowing, sex. After we'd happily dated for 2.5 years, I chose to change pills, on my doctor's advice, to avoid a common and unpleasant side effect (and I haven't had a yeast infection since, woo hoo!). My new pills, however, seemed to cause serious mood swings. After yelling at a homeless gentleman because he asked for change (I later apologized), I decided to take a break from the pill. My partner was supportive, perhaps hoping to avoid my mood swings himself, and agreed to wear condoms as part of the rhythm method.
Not for long. Shortly after going off the pill, I lost interest in sex with him, and could no longer orgasm with him. I did not lose interest in sex, however - though I never cheated, I suddenly felt attracted to other men, one of whom I'd worked with closely for many years and never considered particularly attractive. About a year later, my fiance and I ended the relationship. He's a great guy, btw, handsome and smart and also naturally monogamous, and a French chef; he has since married a gorgeous, delightful woman, has kids, etc. Oddly (for me), I have never been even slightly jealous of their relationship; I suppose jealousy is a primarily hormonal reaction as well. I do miss his cooking.
At any rate, I've always felt like I was a "bad person" for losing interest in such a great guy, the whole episode caused a lot of pain. But this study makes me wonder if I can just blame the whole thing on the pill! Still, though, it's a fabulous and effective form of birth control. Consider recommending that couples go off the pill for some time prior to marriage. If we'd been married, or had kids, I probably would have stuck it out and gone without orgasms the rest of my life.
Hahahahahaha....NO. Most girls when they first begin to use the pill are contemplating a sexual relationship with the man they have picked. 8 times out of ten, the guy dumps the GIRL.
Reply | Report Abuse | Link to thisYou should be ashamed for publishing the scent article like it's new information. I wrote about it in 2000 and it's been old news for years, that women prefer next of kin scents when they're on the pill.
Reply | Report Abuse | Link to thisOnce off it, they go for the MHC that's not like their own.
Pheromones of the opposite sex have been isolated: one says "keep away", so men who smell (subconsciously) other men's scents in the bathroom use another stall.
Women go right ahead and use the toilet.
Pheromones also brighten moods: one scientist had a flask filled with skin cell extracts from skiiers who hurt their needs. When he opened the flasks, usually somber women said "let's eat pizza, let's play cards."
I don't think you can make any generalizations about how this will affect women's relationships because supposedly the same kinds of fluctuations in hormone levels occur across menstrual stages... and you don't see women leaving their guys halfway through every month.
Reply | Report Abuse | Link to thisWaaaait a minute here. The Pill does not stop ovulation. If it did, there would be no instances of pregnancy on birth control, which we all know can happen. The hormones in the pill thin the uterine lining enough that if fertilization occurs, the egg cannot implant itself, ergo, cannot grow.
Reply | Report Abuse | Link to thisAnd what about when a man has a vasectomy? That changes some major hormones. It really should be common knowledge by now that women get moody from hormones, so let's not start blaming the pill, which regulates them, alright?
i did see my sister go from a happy healthy young girl dating her boyfriend to a fatter moody depressed person after two years of birth control. i have seen others' periods go insane. i would never subject myself to any of that 'guinea pig' nonsense...haha and those certain ads on the tv that suggest to be careful of the risk of stroke/death...people are nuts...just get married and have kids or DON'T....ha luv MeL.
Reply | Report Abuse | Link to thisWhile the article is interesting, science has been playing up the idea that we are just the sum of the chemicals running through our brains, and that monogamy, even homosexuality is not choice, but merely a reaction to the various chemicals shooting through our bloodstream, the content and levels of which we are helpless to consciously control unless we start popping pills. The concept of saying "I'm sorry I cheated on you, baby, it was these damned pills!" Is ludicrous. In the end, a person's actions ARE ultimately a matter of their personal choice. We seem to be drifting away from the concept of personal choice, and more in the territory that we are nothing but chemical marrionettes...
Reply | Report Abuse | Link to thisI think the whole system and levels status of the idea of Love is messed up and should be reworked and updated - first thing being some new words for the varieties.
Reply | Report Abuse | Link to thisAnd hormones will prove fascinating something like colors_
A very good article! Well done especially because humans tend to think they outrule nature. The fact that we now have come to techniques that can harvest so much data about the intimate lives of women. There's so much to explore.
Reply | Report Abuse | Link to thisOne thing I know is that having children enhances your smell and senses; and that body odeur does make a difference. In the most apparent way it tells you how healthy a man eats and thus takes care of its body. Very important information. Sorry guys! I believe we uncounciously smell a lot of information. But it would be nice to hear if the other ways around works too; or that the cliche is true. Man don't care much.
I'm not sure why this old article showed up in the most read column, but I'm going to comment on it anyways. This piece is terrible. I'm sorry, but the finding does not demonstrate that the pill affects women's smell preferences.
Reply | Report Abuse | Link to thisThe article is freely available here: http://rspb.royalsocietypublishing.org/content/275/1652/2715.full
In the study, the authors had two groups of women smell men's shirts. One group of women then started taking the pill for a few months, while the other did not. On a second test day, the authors had both groups come back in to smell a new set of shirts.
The key results are all there in figure 2. It is quite clear that women, whether those who started taking the pill after the study started or those who never took the pill, had little preference for either similar or dissimilar genotyped men at the second time point. However, at the first time point, women who would soon begin to take the pill had a much stronger preference for dissimilar men than women in the control group. In other words, this result is solely due to the fact that the control and experimental groups had different baseline preferences of men's smells. This is hugely important, as at the baseline test, none of the women were taking the pill!
The best explanation of this result is regression to the mean. Take a look at figure 2c, which is women's rating of the desirability of male scents. Notice how at the first time point both control and experimental groups have extreme values in opposite directions. And yet, at the time of this test none of them were on the pill. At the time of the second test, after half of the participants began taking the pill, ratings of both groups appear to have regressed towards less extreme values near 0 (no preference). This is a classic example of a purported finding which almost certain has come about by chance.
So what's all the fuss about? This is a non-story.
Most women in America, since the 70's, are put on the pill as teenagers. There is not "family" or "relationship" involved. The parent (often the mother) makes the single-handed decision to put her daughter on the pill. The daughter often has no say, and/or is only told good things about the pill. Being on the pill is an implicit expectation of and permission for promiscuity and sexual experimentation. The first poster spoke of the heartache involved in this: a too often overlooked side-effect of oxytocin--the "binding" hormone released with orgasm. Too often, again, the teen is never told of the risks of STDs. That is why 1 in 4 teenage American girls has an STD. For many reasons, the pill leads to broken relationships and erosion of the social fabric.
Reply | Report Abuse | Link to thisIs your research published somewhere? I would like to read it. Thank you.
Reply | Report Abuse | Link to thisI did not find "cheat" offensive. It means "to betray the beloved's trust," since this gift of self in the sexual embrace was traditionally considered a one time, exclusive gift.
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