Thalidomide is a medicine that was developed in the 1950s as a sedative. It was used later against nausea in pregnant women, but this resulted in the birth of about 10,000 infants with deformed limbs, and sometimes with other serious problems such as blindness, deafness, and heart problems. More than half of these children died. This crisis led to more structured regulations for the development and use of medicines. Currently, thalidomide is used to treat certain cancers, and to alleviate symptoms of leprosy.