Nowadays, if a woman thinks she may have a bun in the oven, it only takes ten bucks and a couple of minutes to get an answer from the privacy of her own bathroom. But it wasn't always so. Back in the day, people used everything from barley to bunnies to predict pregnancy, often with surprising accuracy, and sometimes with devastating ecological consequences. And of course, lots of urine. Lots of urine.

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The Ancient Egyptians, for example, had a fun way of determining pregnancy. The lady in question peed on a pile of wheat and barley seeds, and if over the course of several days the wheat sprouted, she could expect a girl, and if it was barley, a boy. Interestingly enough, researchers tested this method in the 1960s and found that it was 70% accurate. At least at the sprout, no sprout, baby, no baby part. The baby's gender part; that was total bunk. It may be like all the extra estrogen in the urine that helped the grain to sprout.

In medieval times, physicians got really into eyeballing pee. They could allegedly determine pregnancy either by examining the color or clarity of the urine, and sometimes mixing it with wine to see what happened. We're not sure about the accuracy of these methods, but since alcohol does react with certain proteins in urine, these guys may have been on to something.

In the 1900s, researchers started honing in on the concept of hormones. They began to notice a pattern of fluctuations throughout a woman's 28-day menstrual cycle, and saw a sharp spike in the level of HCG, human chorionic gonadotropin, in pregnant women and nowhere else, so basically, they discovered a certain amount of this hormone indicated pregnancy and that it was key to accurate testing. Today's tests still work by measuring HCG.

But, throughout the 20th century, other methods were explored. The A-Z Pregnancy Reaction test popped up in 1928 and was the first of several bioassays, or animal-based tests. named for German researcher Selmar Aschheim and Bernhard Zondek, the patient's urine was injected into a baby female mouse or rat. If the animal suddenly went into heat despite being sexually immature, it was assumed that the woman was pregnant and her hormones were kicking off an early estrous cycle for the rodent.

Then came the rabbit test and with it a new euphemism featured in such timeless cultural beacons as M*A*S*H and Aerosmith songs: "the rabbit died." This popular phrase morbidly indicated that a lady was in the family way, and referred to the Friedman Test, which involved injecting yes, pee into a female rabbit. But the term "the rabbit died" is misleading because every rabbit in fact died, not because mom pee killed them but because the doctors did.

Lab animals back then were considered even more expendable and the quickest way to see results was to euthanize and dissect bunnies to look at their ovaries. The HCG in the pregnancy urine triggers what's known as corpora hemorrhagica, a temporary growth on the rabbit's ovaries easily spotted by prodding doctors within 48 hours of pee injection.

Then came the Hogben or "Frog Test", named for the British biologist Lancelot, yes Lancelot Hogben. This test traded bunnies for African Clawed Frogs. The test carried on a familiar theme: inject some urine and see if the female frog starts to ovulate.

During the Baby Boom of the 1940s and 50s, demand for pregnancy detecting frogs was high and tons of African frogs were exported all over the world. Because female frogs naturally lay eggs that are visible to the human eye, the frog test had the advantage of not killing the animals, so consider it. So when the test became obsolete some clinics released these little Freddie Krugers into the unsuspecting wild with totally disastrous results. Because man have those frogs gotten their revenge!

See, these invasive clawed frogs carry and transmit a nasty fungus known as BD that causes the deadly and untreatable disease chytridiomycosis. Now, it's not dangerous to us, but this thing is wreaking havoc on native amphibian populations and has been the cause of massive decline, endangerment, and extinction of over 200 species worldwide.

Luckily, pregnancy tests kept getting better, cleaner, faster, and cheaper over the decades. For a while, blood tests were the best way to do it, but even that took several days and necessitated a visit to a clinic. The first home pregnancy tests hit the American market in the late 1970s and while they were revolutionary, they resembled chemistry sets full of bottles, mirrors, tubes, and vials of sheep's blood, and weren't the most user friendly things.

But things finally got easy and efficient in the late 1980s when the first modern pee-on-a-stick tests hit the shelves in drugstores everywhere. They used tiny strips of fabric infused with antibodies that detect the HCG hormone and basically have taken the guesswork out of everything.

It's easy to forget all of these modern conveniences and the weird things that we had to do to get to where we are now.

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