Chilean President Michelle Bachelet has announced plans to end a total ban on abortions in the predominantly Roman Catholic country.
Ms Bachelet has tabled a bill in Congress to legalise abortion in cases of rape or when there is a threat to the mother's or the baby's life.
Abortion is punishable in Chile by up to five years in jail.
The absolute ban of abortion puts the lives of thousands of Chilean women at risk every year, said Ms Bachelet.
She went on national television to announce the plans.
"Facts have shown that the absolute criminalization of abortion has not stopped the practice," she said.
"This is a difficult situation and we must face it as a mature country."
The BBC's Gideon Long says the draft law faces opposition from Chile's powerful Catholic Church, from conservatives in Congress and from some inside Ms Bachelet's own coalition, led by the Socialist Party.
Pinochet's abortion ban
Ms Bachelet's proposal would allow abortion to be carried out up to the 12th week of pregnancy if the mother's life is at risk, when the foetus is so badly deformed that the baby wouldn't survive or in cases of rape.
For girls up to the age of 14, termination would be legal until the 18th week.
Ms Bachelet said younger girls might take longer to realise they are pregnant.
The absolute prohibition on abortion was introduced in 1989, in one of the last acts of Gen Augusto Pinochet's 17-year-long military rule.
"Chile had an important legal and public health tradition, interrupted arbitrarily in the last days of the dictatorship," said Ms Bachelet.
"Twelve bills [to decriminalise abortion] have been tabled in the Chamber of Deputies and the Senate since 1991," she added.
Polls say most Chileans support the legalisation of abortion on Ms Bachelet's terms, but previous proposals have been rejected in Congress.
Most Latin American countries severely limit access to abortion. A total ban is in place in seven of them: El Salvador, the Dominican Republic, Nicaragua, Honduras, Haiti, Suriname and Chile.