Sniffing out sexual compatibility

What information is emanating from your armpits and what does it reveal to a potential partner about you? With Kat Arney to discuss couple-compatibility is Robert Winston, Emeritus Professor of Fertility Studies at Imperial College London...

Kat - Now, Nate mentioned some signals to help boost your chances on that crucial first date, but what about other signs? Could you be emitting information maybe from your armpits without realising it? what would a sniff test reveal about you? So with us, to discuss some of these more intimate issues of couple compatibility for producing babies is Robert Winston again, emeritus professor of fertility studies at Imperial College London. Hi, Robert.

Robert - Hi.

Kat - So, tell me a little bit about the smell of love. What do we know about what attracts people in terms of their smell?

Robert - Well interestingly, pheromones as may like, you smell them. I mean, they may be imperceptible but it's being clearly shown by a number of people, Craig Roberts for example. Also incidentally at New Castle University for some strange reason. And Craig has shown in his rather nice work that - I mean, one experiment we did together many years ago was to take t-shirts which should be worn by young women, undergraduates who I haven't met sadly who have slept in these t-shirts for two nights at their menstrual cycle. They were not on contraception, they were not eating curry, not smoking, not using spicy food.

Kat - Didn't have bad BO.

Robert - And then I had to sniff them in a blind test. And I used the word advisedly and rank them in order. Actually, what was interesting was, completely blind because I had been tissue typed and so had they, it turned out that the ones whose tissue type was most compatible with mine, those were the pheromones I least liked while the people who hada very different tissue type I scored quite highly in a completely blind test. So, it's quite a nice example I think of how pheromones may work.

Kat - Obviously, smelling someone's horrible sweaty sporty BO is a bit of a turnoff and there's a huge industry in people spraying on perfumes and all kinds of things to cover up or change their smell. Is that interfering? What would be the most attractive smell to find or the best way of finding the right smelling partner for you?

Robert - Well, I think we should ask you that but I don't know. I mean, I think we have to be very careful about drawing these conclusions. But of course, don't forget that quite a lot of people find the smell of people not unattractive particularly in times when they're making love. I think that it's not very simple. It may well be that in public places, we find those sorts of smells quite disgusting. But I think what I think is interesting about pheromones is that you don't need to actually be able to smell with your olfactory system in the usual sort of way because the olfactory system is extraordinarily sensitive. You can detect one part in several hundred million of a molecule. so, it is extraordinary in how we do that.

Kat - In terms of finding this kind of compatibility if you're thinking about making babies with someone, is it a way of making sure that you're going to make compatible babies or even be able to make babies at all?

Robert - Well, that's a theory. The theory of course is that if you are genetically just similar, you're less likely to have a mutation which is recessive which is the same allele of both partners. That's the theory and certainly, we do know that people who married to similar people are less likely to have deformed or genetically damaged children. so, there's some evidence for that.

Kat - In terms of fertility and trying to make babies with someone hoping to be compatible with them, are there any signs that maybe people could look for to see if someone is fertile that they might want to have babies with? He has a deep voice. For men, we heard about changes in women, big hips. What are some of the estimates?

Robert - I don't know, but I would say that the best way to find out whether somebody is fertile is to have sex and have sex often. And not necessarily the mid cycle by the way because of course, although it's been staged on this programme just how ovulation occurs on the 14th day of cycle, but throughout the cycle, but doesn't always and sometimes people can even ovulate during menstruation. It's not quite as straightforward as we sometimes kind of put out.

Kat - Yeah, I mean the inside of a lady's body isn't made of clockwork.

Robert - Nor a man's either.

Kat - So, in terms of, if you are trying to make beautiful babies if people are in the mood this Valentine's Day, are there any things that they could do maybe that they could eat or ways that they could try and boost their chances?

Robert - That's what it's about. It's about Valentine's Day.

Kat - Well, maybe you just feel like love all the time, but...what could boost people's chances of conceiving if they want a Valentine's baby?

Robert - Have a drink.

Kat - Not too much though.

Robert - Well, you know, that's another myth because in fact, we had all these dreadful headlines stuff going about alcohol now on pregnancy. But actually, the evidence that alcohol in moderation is in any way dangerous to pregnant women is very, very dubious.

Kat - I'm talking more about, if you have too many, just pass out before you can get to it.

Robert - I mean, I think we all want to have consensual sex. No, I don't. I mean, that's a different issue.

Kat - But if you're going to a restaurant, is there...

Robert - Yes. But I think going to a restaurant, having a pleasurable occasion is all part of loosening those inhibitions. I mean, what is quite interesting and we did some research many years ago where in a large cohort of infertile women who are undergoing various treatments for infertility, not only IVF. What we found was that people who had regular orgasm were actually less likely to be infertile. Moreover, if they were infertile, they will usually have a specific cause for their infertility. People with unexplained infertility often were more likely to unorgasmic and that would suggest that orgasm and contraction of the genital tract may have something to do with fertility. So again, pleasure with intercourse.

Kat - So, having lots of fun if you're out there having a fun Valentine's Day. Thank you very much. That's Robert Winston.