In 1931 the Friedman test, more commonly known as the “rabbit test,” was developed to determine human pregnancy. The test was carried out by injecting 10 ml of a woman’s urine into an unmated female rabbit. Forty-eight hours later, the rabbit was killed and its ovaries examined. The presence of hemorrhage spots on the ovaries indicated that the woman was pregnant. By the late 1960s, the test was made obsolete by the introduction of laboratory blood tests. Soon after, the pregnancy euphemism—killing the rabbit—disappeared from common usage.