Rabbit test


 * For the 1978 film directed by Joan Rivers, see Rabbit Test (film)

The rabbit test was an early pregnancy test developed in 1927 by Bernhard Zondek and Selmar Aschheim. The original test actually used mice. The test consisted of injecting the tested woman's urine into a female rabbit, then examining the rabbit's ovaries a few days later, which would change in response to a hormone only secreted by pregnant women. The hormone, human chorionic gonadotropin (hCG), is produced during pregnancy and indicates the presence of a fertilized egg; it can be found in a pregnant woman's urine and blood. The rabbit test became a widely used bioassay (animal-based test) to test for pregnancy. The term "rabbit test" was first recorded in 1949 but became a common phrase in the English language. Xenopus frogs were also used in a similar "frog test".

Modern pregnancy tests still operate on the basis of testing for the presence of the hormone hCG. Due to medical advances, use of a live animal is no longer required.

It is a common misconception that the injected rabbit would die only if the woman was pregnant. This led to the phrase "the rabbit died" being used as a euphemism for a positive pregnancy test. In fact, all rabbits used for the test died, because they had to be surgically opened in order to examine the ovaries. While it was possible to do this without killing the rabbit, it was generally deemed not worth the trouble and expense.

In popular culture

 * The rabbit test was featured in the episode of the television series M*A*S*H entitled "What’s Up, Doc". A rabbit (Fluffy) belonging to Radar O'Reilly was used to test for pregnancy in Margaret Houlihan. To assuage Radar, rather than killing the rabbit, Hawkeye Pierce performed surgery under anesthesia. When Houlihan later thanked Radar for the use of his pet, he responded that he was sure that she would have done the same for the rabbit.
 * The Aerosmith song "Sweet Emotion" refers to the test: "Can't catch me 'cause the rabbit done died."
 * Country singer Eric Church also references this in his song "Two Pink Lines" saying "these days the rabbit doesn't die"
 * In the BBC comedy The Vicar of Dibley, in a purposefully absurd variation of the rabbit test mixed up with home pregnancy test kits, Alice Tinker Horton tells the vicar she can't be pregnant because she "wee'd on a hamster" and it didn't turn blue.
 * In the I Love Lucy episode when Lucy finds out she's pregnant with Little Ricky, she telephones a friend and excitedly reports, "The rabbit died!"
 * In an episode of The Golden Girls, Sophia Petrillo claims that she believes she is pregnant. Her daughter's response is, "What happened? The rabbit died laughing?"
 * An independent short film titled Redemption Maddie centers on the idea of testing pregnancy with rabbits.
 * In Squidbillies, the rabbit test was used to determine if Early was pregnant. However, the rabbit died when Early's acidic urine "melted" the rabbit into an ooze, rather than as a result of the test procedure.
 * Billy Crystal starred in a 1978 movie Rabbit Test in which he became pregnant.
 * A collection of essays by Teresa Bloomingdale, columnist and mother of ten, bears the title I Should Have Known It When The Rabbit Died (1979). The title refers to an anecdote (1956) in which the rabbit used in her first pregnancy test died from jumping off the examination table, thereby shrugging off any responsibility for her ever-growing family.
 * In Philip K. Dick's novel The Game-Players of Titan, pregnancy is tested by biting a strip of "rabbit paper".