Modern pregnancy testing kits are cheap and easy to use. Many
claim to be 99% accurate. They sample urine or blood and detect
chemical markers associated with pregnancy that are found in
these fluids. Older testing methods were often based on
superstition and false assumptions. Urine is the common thread
linking many of them with test kits of today. Ancient Egyptian
texts describe an early urine-based test in which the woman
urinated over a mixture of wheat and barley seeds. A boy was
expected should barley grow. If wheat grew it was a girl. No
growth meant no pregnancy. Other tests from the Middle Ages
onwards tried to detect ‘something different’ in the urine. They
looked for changes in its appearance, smell and taste, the way
it reacted with other substances, and the colour with which
urine-soaked cloth burned. These all claimed to diagnose
pregnancy - or the lack of it. Specific hormones associated with
pregnancy were identified in the 20th century, and this led to
increasingly refined chemical tests to d