Mifepristone

Mifepristone is a synthetic steroid that is used as a drug. It can be used to cause a medical abortion in the first two months of pregnancy. It can also be used as an emergency contraceptive. It is often known as RU-486, the name it had in early tests. It was discovered by Roussel Uclaf in France in 1980. 
When it is used for an abortion, it is usually combined with another drug.