It's after the pontiff declared 2016 would be a Holy Year of Mercy, where priests will be given authority to forgive mortal sins.
Women who have an abortion and doctors who perform them can, in some circumstances, be excommunicated from the Catholic Church.
Next year for the first time, priests will have the authority to forgive mortal, as well as venial (lesser) sins.
Pope Francis has said the church must be "an oasis of mercy", and that "The Church's very credibility is seen in how she shows merciful and compassionate love."
An Italian cardinal, Velasio De Paolis, has said the Catholic Church still recognises abortion as a sin, and hopes Pope Francis' announcement does not cause confusion.