Posted by Frankie on April 27, 2000
In Reply to: The rabbit died posted by Bill Rodgers on April 27, 2000
: : : Where did "The rabbit died" come from?
: : Back in the old days, rabbits were used in pregnancy testing. I'm a little shaky on the details. So I'll just guess. I think the woman's urine was injected into the rabbit. The animal was killed and examined. Maybe someone else has better information. Is there a doctor in the house?
: : (How about this for a pregnancy phase -- "wearing her apron high.")
: You've managed to surprise me ESC. Why post a contribution which implies such gross cruelty to animals when, in truth, it simply didn't happen like that. I'm reluctant to be dogmatic without further research but it was an extract from the urine which was injected and it wasn't necessary to kill the rabbit to determine whether or not the urine sample came from a pregnant woman.
:From the FDA website----Now regulated by the FDA, pregnancy tests have come far since the early to mid-1900's when toads, rats and rabbits were used in testing. Now, over-the-counter home pregnancy kits can detect pregnancy as early as six days after conception. All pregnancy tests are based on the presence of a hormone, human chorionic gonadotropin (HCG), that the pregnant woman produces after conception. The hormone is however poisonous to toads, rats and rabbits. A blood or urine sample injected into the small animal would kill the creature if the hormone was present.
Hence "The rabbit died ---you're pregnant". Unfortunately not accurate because the small animal could have died do to a blood disease present in a woman who was not pregnant.
The first self tests of the 1970's used ring, or "tube agglutination," tests consisting of prepackaged red blood cells to detect HCG in urine. A ring at the bottom of the tube indicated a positive result. Sensitive to movement and human error, ring tests are now rarely used.
Today's brands, such as e.p.t. and First Response, contain monoclonal antibodies that detect minute traces of HCG. These antibodies are molecules coated with a substance that bonds to the pregnancy hormone, if it's present, to produce either a positive or negative result.