Until the mid-1960s, a woman in London who suspected she might be pregnant could ask her doctor to send a vial of her urine to a townhouse on Sloane Street where it would be injected into a tropical frog. (The frog would probably have been captured in South Africa and shipped to the froggery; Xenopus laevis was difficult to breed domestically.) If, post-injection, eggs popped out of the frog, the woman was pregnant. The results of the Hogben test were surprisingly accurate (..)
