How Did Frogs Become A Pregnancy Test For Humans?

Pregnancy tests are an invaluable tool that can help us keep expectant parents and their baby's safe and healthy in the early stages of pregnancy, you know, when the more obvious signs and symptoms of yet to materialise. It figures then that we were quick to capitalise on a remarkably reliable way to confirm using just a urine sample if someone was pregnant or not, but I wasn't expecting, however, was that this test was basically a frog. Yep, there was a time not that long ago that getting the good news involved a brief interim so that someone somewhere could inject your pee into the body of a frog and see if it produced eggs. We've moved on since then, but as I'm about to discuss with London Natural History Museum's research leader in collections and culture, Dr Isabel Davis, it's good to remember this technology the past for reasons beyond our curiosity. My name's Rachel Funnell and this is We Have Questions. So hello, Isabel Davis, it's so nice to have you on the podcast today. Thank you for having me. I was wondering if we could kick off with you just telling us a bit about yourself and what it is you do at the London Natural History Museum. Yeah, so I'm what they're calling a research leader in collections and culture, which means that I coordinate one of the nine science themes at the Natural History Museum. And collections and culture is code really for arts and humanities research, so I look after everything from kind of history all the way through to creative practice, you know and everything in between really, so yeah, wow, it must be very expensive. I imagine you get to see a lot of cool stuff. Yeah, definitely, yeah, I mean, it's a kind of problem in the sense that my role doesn't stop anywhere, but it is that anything could come at me, you know, like woodlies or one-bats or butterflies or, you know, one day it's one thing. Yesterday it was tigers, you know, obviously today it's frogs talking to you, another day it'll be something else, you know, but he's got to keep it varied, I like it. Yeah. So we were part of the team that has been working on the new gallery fixing our broken planet. So what can people expect from this gallery? Yeah, well, I mean, I think one of the things that strikes me, I just went in there this morning and it's incredibly specimen rich, you know, and you go, you walk through and they're really displayed rather like religious shrine objects, you know, it's really beautiful, like, oh, that the little niches are in or kind of backlit and you can really see the detail on the specimens that they've chosen. And there's some really kind of stand out beautiful things like the Marlin that you see as you come into the gallery, and there's a huge bison at the end, but also just the little things, like little starfish and jellyfish and, you know, obviously my frogs, they're just beautiful, how they've done it. The minerals look fantastic, all twinkling in the lights. Yeah. Yeah, it is staggering when I was reading of the kind of range of things that are on display now. And, you know, they cover some really important messages and there are some really curious specimens among them, but of course, we've brought you here today to touch on one in particular. That frog, we need to talk about the pregnancy test frog, what can you tell me about it? Yeah, well, so I'm a cultural historian and so I was working on a history of human conception and really thinking about pregnancy diagnosis as part of that. And when I heard about the fact that in the middle of the 20th century frogs were the main pregnancy test, I just thought, well, what, how was that? And what was that like, if I was trying to picture it, and I decided to, you know, kind of go and find out more about it. So I went to the family planning association archive, which is held at the Welcome Collection in London. And I found these files, which were all about the logistics of moving these tropical toads from South Africa to the UK. So the family planning association was just that they had one of the labs that ran in the UK. They opened their lab in that 1948, but there were NHS labs just before that and before that there were other labs in the UK that were doing this testing. So from the 1930s to the 1960s, it was the main way that pregnancy tests were done, so people would send their urine sample by post through their doctors or pharmacy and they'd be injected into these frogs. And if you were pregnant, the frog would lay eggs. Yeah. What's done to you? It's just staggering, I mean, I'm really surprised to hear about the date, because I don't know when it is I thought that modern pregnancy tests came into play, but I didn't think it would be testing by frogs sort of that recently, it doesn't for a long ago, yeah. Yeah, I think that's one of the things I thought as well as a historian. It doesn't feel very modern, I mean, this is modern history and it is strange. And I mean, before the frogs, there was another animal test which used mammals and particularly mice, but of course, you've got to dissect the mouse to get the result. So frogs are an advance in the sense that you can reuse them. You don't need a vivisection license, and because they lay eggs externally. So the kind of principle was discovered through hormone testing and like research on human hormones and mammalian hormones. So yeah, the frogs were, the frog test was really developed in Cape Town in South Africa, and they were the local frog, and they were also good for studying embryology and reproduction because they have very large eggs and have very large embryos and so they're kind of useful in that way. But yeah, it doesn't feel very modern, and I guess they did have other, you know, like a chemical pregnancy test earlier, but the problem with the chemical test as it took, it was very difficult to read. So you had to have very specialist readers, the results were a little bit ambiguous. And so it took time to get those tests to the same accuracy level as the animal tests. I mean, yeah, so that's just incredible, so these frog tests, they were pretty decent. Do you know what the accuracy level was, or how it compares the sort of modern testing? It was really good, and I think they say it was about as accurate as modern tests are, but the problem with them was it took more time. So first of all, now you can even take a test before your period is due, but then it was really sort of two weeks after your period was due. And so, and of course, you would do things by post as well. So you've got to send your sample in, obviously, then it's tested, and then you have to go and get that result from the doctor. So it wasn't thought that it would be right for women to get their own results. People feared that there would be maybe an abortion epidemic. And so, you know, you had to go to your doctor to get your results, so doctors had to kind of mediate the result. So there's a lot of kind of societal things to think about as well when you consider the access, because I was wondering, like, you mentioned it's an NHS lab, does that mean that it was quite widely available to women if they wanted to get tested? Well, not really, so you only really had a pregnancy test in that period if you really needed one for some reason. So most people just waited and sort of saw, I mean, of course, there are some pregnancies that people don't really have any doubt about. And, you know, you just know you're pregnant, and it can be confirmed quite straightforwardly. But so the pregnancy test we're really used in hard cases of different kinds. So cases where there was some kind of confusion, maybe somebody, you know, didn't have periods or had very disruptive periods, or they were breastfeeding, or they were in denial, you know, some of these sort of young girls who said they weren't pregnant. Most people just sort of hung around and waited, it just wasn't really something. It wasn't as sort of routine as it is now. We wouldn't think about continuing without a pregnancy diagnosis quite early on. Most people would sort of do that really quite quickly as they suspected they might be pregnant. So it's just a really different sort of paradigm shift, I guess. But yeah, these sorts of societal things were the things that interested me because, of course, we're looking at the early apartheid period in South Africa. So the discovery is made before apartheid, but we're really looking at a time when South Africa was a dominion of the British Empire. So it's self-governing, but it's still part, you know, sort of in the universe of the British Empire. But, you know, the politics of that were that the majority black population were disenfranchised and that paved the way, laid the ground for the apartheid government to come in in 1948. And this is a trade, it's an example of a trade which directly benefited that government. And of course, they didn't share the benefits of that with everybody equally. In healthcare perspectives, we got to think about the fact that this really, you know, obviously benefited white women in the UK. Maybe people with other cultural backgrounds in the UK and white patients in South Africa. But in some parts of rural South Africa, it can be hard to get the pregnancy test now. And so the thing about knowledge and like progress, it's like progress, yes, but for who? Who is the knowledge shared with? And just that thing as well about women not getting that knowledge straight into their own hands. You know, and the fear of what women might do is they got an early pregnancy test, a definitive early pregnancy test result, says something, doesn't it, about the trust that it's placed in people and how knowledge is shared or not shared. And so that was the sort of thing, I guess, that I was interested in partly because the pregnancy test is a knowledge technology. You know, it's the demand for pregnancy certainty which drives this trade. I mean, hundreds of thousands of frogs are moved. I could typical consignment for one lab would be at 500 frogs, so they're moving them in large quantities. And this was just one specific kind of frog. It's not a test that would work on different neurons. They do use other frogs, so sometimes there are shortages, you know, so there's a drought or some other reason where they can't collect enough of these frogs, at the, at the, at that point, there's a collecting them from the wild. They're quite difficult, I understand, to breed in captivity, they're collecting them from the wild and when there are shortages because of whether or other things, they do tries, certainly the family planning association tries to use local British frogs and they do get some results, but they're not as sort of definitive, I don't think, they don't find them as good and they actually use male frogs as well. So female frogs will lay eggs and they seem to particularly go for female frogs, but if you have male frogs, they will produce sperm and so they did sometimes use the male frogs as well, but I think, I think it must be that just like the results are not as good or not as clear. Yeah, that's really interesting to hear and I mean, even also with the, the fact that it works for both sexes, so do we know what the mechanism is as to why it is injecting the urine of a pregnant person, brings about these changes? Yeah, so it's a particular hormone, human, chorionic, gonadotrophin, which is the same HCG, which is the same hormone which our pregnancy tests now detect and I mean, it's worth saying of course that that it's testing for the hormone rather than a viable pregnancy and so I mean, one of the things that we often don't really think about is the fact that the pregnancy test will still show positive if you've recently lost that pregnancy because the hormone went to have kind of dissolved immediately, that it takes time for it to disperse, but exactly how the hormone operates on the, you know, why it makes this ovulation effect, I'm not completely sure, but yeah, with mice and they would dissect them and they found that they would have an ovarian response, but they would have to use more than one mouse as well for each test, so it was very wasteful. Yeah, it's interesting to hear because I feel like the idea of using things from nature is not unusual, we do it in so many different ways, but here it's almost like the whole animal being a test is direct, yeah, and it almost seems too perfect that you just inject the urine and it lays eggs in, hey presto, there you go, like it's really remarkable, you'd expect to have to put it in the blender or do something and process it in some way. Yeah, it's incredible, and you know, for two animals that's so distantly apart, evolutionarily, but this hormone, you know, brings about change in a frog that exists in a human, it's incredible, I mean, are they still used any more in this way or is this fall and out practice? I don't think they're used for pregnancy testing because there's so much better mechanisms, but the fact of there being the main pregnancy test animal did feed them into, so they're really an important experimental biology specimen, you know, so labs will still have xenopus keep them. I think, you know, I don't know so much about how they're sourced, but I presume now that they are bred rather than collected from the wild. Yeah, so they're still in use, they're very old frog, but it is this thing about laying large eggs, which makes them so useful for studying embryology, but aviparasanemals have always been a kind of natural laboratory for thinking about mammalian reproduction, so obviously birds, as well, and fish, and frogs, you know, and insects have been, you know, from earliest times that Aristotle talks about opening the eggs of chickens one a day, so that you can see the development of the embryo of time, you know, and we see those drawings of the inside of chickens' eggs, you know, in anatomical drawings from, you know, at least the 16th century, I think, so yeah, interesting. I'm definitely getting real envy for your job, this seems like such fascinating stuff to sort of go and dig into and find out about. How does it tie in with the sort of broader gallery? Yeah, I suppose, my work is very much about how nature and culture interact, you know, and obviously it's, you know, there's a story here about how human health has impacted on wildlife, so obviously these frogs have been moved and that's created factors of disease. You know, actually there was a concern in the 30s and 40s from South African conservationists that they were being kind of irresponsibly overcollected, but actually these frogs in the end have done quite well, and there are, but there are many kind of feral populations, like some in Wales and places like that, and some in Central America, other places, and they take over the habitats of other frogs, and they've also spread like this fungal disease. But I think as well, like there are human costs to experimentation and kind of desire for certainty and progress and technological solutions, and you know, that's that story about hardening inequalities in relation to healthcare in South Africa, for example. And I guess one of the things about the gallery is it's trying to get us to be mindful about the things that we do for ourselves have an impact, and of course, you know, we're always going to want to use natural resources in different ways, but we also ought to do it knowingly. And I guess in a sense, this is a story about supply chains, that we use something here, and global supply chains are so huge, you know, like not only did, you know, is the frog test not that well known today, it wasn't really known in the time that that's how pregnancy tests were done, and that's kind of understandable, like if we go and get a test, a medical test, we don't really know how it's done, but we don't really ask, like where if you source your, I know, your pipettes for your chemicals, so we don't really know how these things happen. And I guess there's an element, trust there, that we trust government regulation, that it's not causing damage, that it's not going to affect the world in a negative way, and I suppose it's, it behoves us to try to obviously inform ourselves about the things we're buying, all the things we're using, but also to try to ask questions about how that regulation happens, and you know, who's going to be held accountable if regulators fail. You know, we are living in a world where it is similar world where they're very, very long supply chains for pharmaceutical companies, you know, people are making, still making a lot of money and monetising, you know, different kinds of health procedures and possibilities, and so, you know, obviously we can't necessarily solve all those problems as individuals, but we can keep asking questions, we can still, you know, keep reading about the impacts and effects of what we do. Like when I was reading the other day about was, you know, this new sort of, there's a, I don't know if it's new, but it sort of crazed for crystals and crystal healing, so that now you can buy crystals in like superdrugs and this kind of thing. But lots of those crystals, and you know, celebrities are filtering their cosmetics through rose quartz. Lots of that is coming from Madagascar, and like artisanal mines, and we might think it brings us closer to nature, to hold rocks, but, you know, there's also questions of ethics there about, you know, how those mines are being run, who's getting the money from them, you know, different, different questions, that people are not thinking about when they're using these things, I guess. Not that it's wrong to use those things, but just, we ought to be aware, I guess, that they'd come from somewhere, they've been dug out of the ground, that's taken resources, and, you know, people have been involved in that. Yeah, so I think that's the lesson to take from this one, this story. Yeah, I mean, I think it's such a good point, because like, what you mentioned there about the crystals, like, in the moment, you're trying to do what you think is a good and like natural thing, and feel, you know, at one, and the intention can be great, but unfortunately, unless you have that sort of step back, think about, well, what is this object? What needs to have happened for it to have been available for me to buy in this store? And I just think as well, with the frog pregnancy test, I mean, on the surface of it, it sounds kind of comical, but I feel like it's such a powerful item, because for most people, you would never dream of connecting something like a pregnancy test to a frog, and to find out all the incredible, you know, innovative ways that we learn to do this stuff, but to remember how it can be connected to all sorts of stuff, I think it will encourage people to think more deeply about it, so I'm really grateful that we've been able to discuss it a bit further today. I was wondering, do you have any other highlights from the gallery that you could share with us? Yeah, I mean, I think there's so many really beautiful things. I think, today, when I was going around, I was really struck again by the birds' nests, which are made partly with, you know, natural grasses and branches, but also bits of plastic. And they're kind of beautiful, but it also tells us something about how closely we live with animals and how their architecture is becoming entangled with ours, and our lives are entangled with theirs. But plastic is such a huge problem that we need to get ahead of, and to try to find some alternative, to try, you know, to push harder really for the removal of plastic waste, and for people not to use one time only plastics. But I just got a nest of robins in my garden, so I'm thinking about birds, I guess, and, you know, it's so sweet to see them, and they live so closely to us. They're quite near the house, you know, the way that robins will come, really, you know, they're very brave birds. But yeah, they're beautiful, the mests, yeah. I always think he's almost like that, a staggering, because I remember a story about, I think it was magpies that have been found using those anti-bird spikes as part of their, oh wow. Because to an animal, like, any object is just another object, they don't know what it's design for, and if they can find a way to sew it in. I mean, there's another thing about how, like, obviously the great Pacific garbage patch is a terrible terrible thing, but that hasn't stopped animals moving into it, because, you know, they don't care, they're just there to find the surface, yeah, but it is your really powerful reminder. I know, like, the animal architecture is interesting in the natural history museum, so the birds nest really attract a lot of artists who want to work on them, because they are really miraculous, like, how they learn to do it, and, you know, the historically they've been really perceived as marvelous, you know, like, how do the birds know how to build a nest, they don't have a pattern, they don't get, you know, they don't get some kind of template, they just start to do it, and they're real kind of motif and metaphor for people about creativity, but because they don't contain bird DNA, you know, they're not themselves birds, they're perhaps more used to artists than they are to scientists, but they're just amazing. And our collection and the curated Douglas Russell, who, it's after them, you know, is just so amazing to visit, and to hear him talk about them, and to kind of see them, and then, yeah, extraordinary, extraordinary collection, and the eggs too, so beautiful. Yeah, I mean, I can't wait to see it. I haven't had the chance to come down to the gallery yet. I know a team of ours came down on the press preview and they said it was amazing, but I fear I may get lost in there for hours if there's this many fantastic stories to explore, and I mean, I know we've touched on that, you know, there's a lot about thinking about your kind of impact on the planet, but do you have any other sort of key messages that you hope people will take away from visiting the gallery? Well, I think I was particularly struck by the mining stories, you know, like, I suppose the message there is that we are going to have to carry on mining, you know, particularly till, until we have enough that we can just keep it recycling, and I think this is something that, you know, people just think on mining is bad, we shouldn't be mining, but we've got to do it until we've got the resources that we need. I guess I suppose I just sort of stand and listen to my colleagues who are working on these topics, and sort of try to listen to what they're saying about that, and what some of the ways of doing that might be that are more sustainable, and I also like the stories and gallery which are about like things which are sort of so small or beneath our notice, you know, it's easy to see the marlin, and it's easy to see the bison, but these tiny little things that you have to really sort of like the cyanobacteria, you know, like who knew this thing was so important, and it's so I'm pre-possessing to look at, and yeah, it's really fascinating, you know, it's been collected over all this time from the polar regions, and yeah, we've got this extraordinary collection of this stuff which just looks like kind of grey dust to me, turns out to be really important. Yeah, it's amazing how often grey dust can turn out to be something very significant. Yeah, definitely, it sounds like you and the team have done a fantastic job of choosing some really interesting things to pop this play in the fixing, er, broken, planet gallery. I'm really excited to get down and check it out myself, and thank you so much for joining me today to talk a bit about these incredible frog pregnancy tests. Amazing stuff. Amazing. Thank you.