Fetal hiccups were reported in 1899, and then confirmed once ultrasound became available. In other words, hiccups may allow the fetus to practise vital 'breathing' motions while protecting it from inhaling amniotic fluid. The theory behind this is that distension of the stomach may irritate the diaphragm and cause it to go into a spasm. However, no one factor has been shown to stimulate hiccups in everyone. A few years ago, researchers reported that they could reliably cause hiccups in four out of ten subjects by stretching part of the oesophagus, but obviously this technique is not a universal hiccup stimulator.
Folk remedies abound for curing hiccups.
A more sinister side of hiccuping appears when they refuse to stop, even after a few days. One poor man, Charles Osborne, lived with continuous hiccups for more than 63 years. He got little sleep, suffered from nosebleeds and vomiting, and was forced to live on a diet of blended foods. But not everyone can weather the consequences of intractable hiccups. Pope Pius XII, for example, is reported to have suffered days of hiccuping associated with gastritis.