SANTIAGO, Chile -- President Michelle Bachelet sent legislation to Congress on Saturday proposing to allow some abortions in Chile, a socially conservative South American nation that is among the few countries in the world that ban abortion in all circumstances.

The bill would decriminalize abortions in three types of cases: malformation of a fetus, a pregnancy posing a threat to the life of a woman carrying a fetus, and conception caused by rape.

Bachelet's proposal is likely to face an arduous debate in Congress, where several opposition legislators and even some members of her New Majority bloc have already announced they will fight the change.

The president announced last May that she would push such legislation. She noted that therapeutic abortions were allowed during the 1973-90 dictatorship of Gen. Augusto Pinochet.

According to figures released by Bachelet, about 16,500 women are hospitalized each year in Chile due to life-threatening complications of pregnancy or because of malformations of a fetus. She said about 500 deaths are recorded each year from fetal malformation.