I was under the impression that it was prescribed for morning sickness.
It was a wonder drug. It was given for morning sickness, but it was the wrong drug for that, it cured the morning sickness, but killed or disfigured the baby. It could also cure a number of forms of cancer. Today most of the cancers that it worked against are curable with other drugs, but many people died because they were not able to get it. It was also used in the tropics as a treatment for malaria.