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Pregnancy test history 101

Pregnancy test history 101

For generations, people have wanted to know if they were pregnant as early as possible. But testing for pregnancy even 100 years ago wasn’t always accurate or easy. Here we share fascinating stories of how people tried to determine pregnancy throughout history (just wait until you read about the onions) and how pregnancy tests were invented.

When were pregnancy tests invented?

Pregnancy tests of some kind have existed in all cultures for thousands of years (don’t worry, we’ll tell you everything). The pregnancy test we know and love, however, hasn’t been around all that long. It wasn’t until the 1920s that scientists began to identify the presence of human chorionic gonadotropin (hCG) in urine.1 And when thinking about home pregnancy tests, we all have Margaret Crane to thank (more about her below) — she designed the first home pregnancy test in 1967.2

How did they test for pregnancy in the 1700s?

“Piss prophets” (yes, that’s what they were called) were popular in Europe from the Middle Ages through the 17th century.1 These were specialists who used the color of urine to diagnose all sorts of things, including pregnancy.1 According to the National Institutes of Health, a 1552 text described pregnancy urine as “clear pale lemon color leaning toward off-white, having a cloud on its surface.”1

How did they test for pregnancy in the 1800s?

In the 1800s, scientists and doctors continued to study urine to try to determine pregnancy.3 In France, doctors embraced the “Kyesteine pellicle” method, believing that you could see an “early pregnancy membrane” — a sticky film that formed on the surface of urine after it stood in a vessel for several days.3 However, those who suspected pregnancy often took matters into their own hands during this time, simply being mindful of physical symptoms, including morning sickness.1

How did they test for pregnancy in the 1900s?

At the turn of the century, physicians, scientists and even zoologists were coming up with all sorts of new ways to test for pregnancy, with the hopes of making the process easier, faster and, most importantly, more accurate.

Rats, rabbits, mice, frogs and toads, oh my!

In 1927, German scientists Selmar Aschheim and Bernhard Zondek developed the A-Z test, which is considered the first test to detect the presence of hCG in urine.3 The A-Z test required injecting urine into an immature male rat or five (!) female mice and if they became, shall we say, frisky (in heat) despite being young, it was believed you were pregnant.3 In the 1930s, Dr. Maurice Harold Friedman developed the rabbit test, noting that if a woman was pregnant, her urine, once injected into a rabbit, would induce ovulation.3 These tests were popular until the early 1960s.3 Lancelot Hogben, a British zoologist, discovered that if you inject urine into an African clawed frog and the frog ovulated within two to eight hours, there was a possibility for pregnancy.3 This test was considered standard for decades. In 1947, Carlos Galli Mainini discovered that a certain species of a male toad may produce sperm within three hours when injected with pregnant woman’s urine, paving the way for more discoveries involving different species of frogs and toads.3

The first hormone pregnancy test

As you can imagine, by the late 1940s laboratories couldn’t keep up with the demand (so many frogs!). In response, a German pharmaceutical company developed a drug called Duogynon.4 According to a 2022 article that appeared in Reproductive Biomedicine & Society Online, “Between 1950 and the 1980s, millions of women worldwide found out whether or not they were pregnant by swallowing tablets or receiving injections.”4 If, after taking the drug, you began experiencing uterine bleeding, that meant you were likely not pregnant. If you didn’t experience bleeding, you were likely pregnant.4 Duogynon and Primodos (which is what Duogynon was called in the UK) have both faced medical and legal scrutiny due to the possibility of birth defects, highlighting the evolving challenges and complexities in pregnancy test development.4

Sheep’s blood and urine

In the 1960s and ’70s, pregnancy testing was available in healthcare professionals' offices with results available in minutes to hours.5 New types of tests used engineered antibodies that were designed to recognize hCG.5 Scientists would attach hCG to sheep’s blood cells, and then mix those blood cells with hCG antibodies and human urine — pregnancy was determined by observing whether blood cells would clump or not.5

A chemistry kit thanks to Margaret Crane

In 1967, 26-year-old Margaret Crane designed the first home pregnancy test while designing packages for cosmetics at Organon Pharmaceuticals.2 Although Crane’s name is on the patent, because she was an employer of Organon, she earned no money.2 In 1971, a company in Canada produced the first consumer prototype using her design.2

The world’s first 30-minute home pregnancy test

In 1985, Clearblue® developed the world’s first “rapid” pregnancy test, which provided an accurate result in just 30 minutes, revolutionizing home pregnancy testing. To use this test, you would pee on a urine sampler and then place the sampler in three separate pots for 10 minutes each. If the sampler turned blue, you were pregnant. Then, just three years later, in 1988, Clearblue® introduced the world’s first ‘lateral flow’ test, a test format that we still know and love today.

Clearblue® continues to be on the forefront of pregnancy test development. In 1996, Clearblue® developed the world’s first 1-minute pregnancy test. In 2003, Clearblue® debuted the world’s first digital pregnancy test, giving a clear result in words. In 2004, Clearblue® offered the world’s first pregnancy test with a color changing tip for easy sampling. In 2012 Clearblue®’s new, innovative, consumer-friendly ergonomic design using Floodguard™ Technology was the world’s first pregnancy test to win a Red Dot design award. In 2012, Clearblue® introduced the world’s first digital pregnancy test with Smart Countdown to your result. And in 2020, Clearblue® developed a pregnancy test with results 6 days sooner than your missed period.6

What are some of the earliest ways people would test for pregnancy?

Long before we had testing backed by science or even “piss prophets,” women had other, more fascinating ways to determine whether they were expecting. While observing physical signs and symptoms has always been used as a tool when trying to determine pregnancy, urine testing has always been considered, even if the methodology was flawed.

Wheat and barley test

One of the earliest records of pregnancy tests using urine can be found on papyri (sheets for writing made from papyrus) from Egypt dating from 1500 to 1300 B.C.E.1,3 According to this theory, if — after peeing on bags of wheat and barley seeds for several days — the seeds sprouted, you were told you were pregnant.1 What’s more, if barley grew you were told you were having a boy.1 And if wheat grew, you were told you were having a girl.1 Interestingly, a 1963 study from Cambridge University found that in about 70% of cases, urine from pregnant women did cause grains to sprout!7 A 2010 study noted that this could be due to increased estrogen in the urine.8

Onion test

Around 400 B.C., the Hippocratic and Hellenic schools in Greece promoted testing for pregnancy by inserting an onion into your vagina and keeping it there overnight.3 Come morning, if your breath smelled like onions, you were told you were not pregnant.3 Why? Because they believed that if an embryo existed it would block the smell of the onion from traveling through your body up into your mouth.3 This test was popular until the Middle Ages (and, thankfully, is no longer in vogue).3

Observing the eyes (and urine!)

In Child-birth or, The happy deliuerie of vvomen, which, at the time, was considered an important contribution to obstetrics published in 1612, Jacques Guillemeau states that a person’s eyes are key to determining pregnancy.9 In the first chapter, which is all about signs to know if a woman is pregnant or not, he notes that a woman may be pregnant if, in the second month, the eyes look hollow and sickly with larger veins than normal in the corners of the eyes and smaller-appearing.9 There is an asterisk at the end of the sentence and in its accompanying note Guillemeau writes that some people can determine pregnancy by looking at the color and consistency of urine.9 So basically, if your eyes look tired and your pee is clear-ish, you were thought to be pregnant.

Today (thankfully!) Clearblue® offers a wide range of home pregnancy tests, all of which are over 99% accurate at detecting pregnancy from the day you expect your period.10 We’ve come a long way from peeing on grains and injecting frogs, and who knows what the future will hold!

Related Articles

  1. Women’s History Month stories: Women who changed reproductive healthcare
  2. Debunking homemade “pregnancy tests:” What you need to know
  3. How soon is too soon to take a pregnancy test?

Sources & Disclaimers

1. National Institutes of Health. Office of NIH History & Stetten Museum. The thin blue line: the history of the pregnancy test. Accessed January 8, 2024. https://history.nih.gov/display/history/Pregnancy+Test+Timeline

2. Catlin R, Smithsonian Magazine. The unknown designer of the first home pregnancy test is finally getting her due. Updated September 21, 2015. Accessed January 8, 2024. https://www.smithsonianmag.com/smithsonian-institution/unknown-designer-first-home-pregnancy-test-getting-her-due-180956684/

3. Lis K. From cereal grains to immunochemistry—what role have antibodies played in the history of the home pregnancy test. Antibodies. 2023;12(3):56. doi: 10.3390/antib12030056. Accessed January 8, 2024. https://www.mdpi.com/2073-4468/12/3/56

4. Nemec B, Olszynko-Gryn J. The Duogynon controversy and ignorance production in post-thalidomide West Germany. Reprod Biomed Soc Online. 2021;14:75-86. doi: 10.1016/j.rbms.2021.09.003. Accessed January 8, 2024. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8648809/

5. Tyssowski K. Harvard University: The Graduate School of Arts and Sciences. Pee is for pregnant: the history and science of urine-based pregnancy tests. Updated August 31, 2018. Accessed January 8, 2024. https://sitn.hms.harvard.edu/flash/2018/pee-pregnant-history-science-urine-based-pregnancy-tests/

6. Clearblue® Early Digital and Clearblue® Early Detection provide early detection of the pregnancy hormone (hCG). Clearblue® Early Digital can detect 78% and Clearblue® Early Detection can detect 77% of pregnancies 6 days before the missed period (5 days before the expected period).

7. Ghalioungui P, Khalil SH, Ammar AR. On an ancient Egyptian method of diagnosing pregnancy and determining foetal sex. Medical History. 1963;7(3):241-246. doi: 10.1017/S0025727300028386. Accessed January 8, 2024. https://www.cambridge.org/core/services/aop-cambridge-core/content/view/14D30302A038355CB787358800D17D44/S0025727300028386a.pdf/on-an-ancient-egyptian-method-of-diagnosing-pregnancy-and-determining-foetal-sex.pdf

8. Erdal S., Dumlupinar R. Progesterone and β-estradiol stimulate seed germination in chickpea by causing important changes in biochemical parameters. Zeitschrift für Naturforschung C, 2010;65(3-4), 239-244. doi: 10.1515/znc-2010-3-412. Accessed January 8, 2024. https://www.degruyter.com/document/doi/10.1515/znc-2010-3-412/html

9. Guillemeau J. Child-birth, or the happy deliuerie of vvomen. 1612. A. Hatfield. Accessed January 8, 2024. https://quod.lib.umich.edu/e/eebo/A02362.0001.001/1:6.2?rgn=div2;view=fulltext

10. > 99% accurate at detecting typical pregnancy hormone levels. Note that hormone levels vary. See insert.


How to use a pregnancy test

When and how you can test depends on the test you use, but in this article you will find everything you need to know before starting a test.