In the past, a unique practice existed where frogs were used to confirm pregnancy, and it was effective in an unusual manner.
The wonders of science are truly remarkable, and the biology of frogs is fascinating.
These slippery creatures serve a purpose beyond being pets or catching flies—they were once used as natural pregnancy testers.
Smithsonian Magazine reports that women utilized the ‘Hogben test’ before the advent of conventional pregnancy tests in the 1970s.
Indeed, over fifty years ago, people employed urine and frogs for this purpose, but to clarify, they were not urinating directly on the amphibians.
Instead, female African clawed frogs were imported and injected with urine into their hind legs before being returned to their enclosures.
If the frog laid eggs, this indicated that the patient was pregnant.
If no eggs appeared, the result was negative.
So, how does this function? The hormone chorionic gonadotropin in humans triggers ovulation in frogs.
In 1938, Dr. Edward R. Elkan documented the test in the British Medical Journal, naming it the ‘xenopus pregnancy test’. He stated, “The discovery of what is now known as the xenopus pregnancy test is based on experiments conducted by Hogben (1930, 1931), who observed that hypophysectomy produced ovarian retrogression, and the injection of anterior pituitary extracts ovulation, in the female South African clawed toad.”
This method proved superior because it previously involved mice, which needed to be dissected to examine changes in their ovaries.
However, frogs were advantageous as they were reusable and could be kept in aquariums conveniently.
Dr. Elkan noted: “Among the 295 tests which I have done so far and in which 2,112 frogs were used I have not seen one clear positive that did not indicate a pregnancy. There were a few negative results which when repeated after a fortnight became positive, but I do not think that these can be regarded as failures.”
Frog-based methods weren’t the only unusual pregnancy tests before modern sticks. The ancient Egyptians had their own method: urinating on wheat and barley. If the grains sprouted, it indicated pregnancy; if not, they just spoiled their crops.