MPs in Ireland are set in a final vote on Wednesday night to introduce abortion in limited cases where the mother's life is at risk.
Irish abortion laws faced global scrutiny after the death of an Indian woman, Savita Halappanavar, 31, in a hospital in Galway in October.
The European Court of Human Rights has ruled that Ireland failed to implement properly a constitutional right to abortion where a woman's life is at risk.
Under a 1992 Supreme Court ruling, women in Ireland are legally entitled to an abortion if needed to save a mother's life - but legislation has never been passed to reflect this.
The Protection of Life During Pregnancy Bill allows for abortion in circumstances where doctors certify there is a real and substantial risk to the life of the mother.
The new bill also permits a termination when one obstetrician and two psychiatrists unanimously agree that an expectant mother is a suicide risk.
Four government deputies voted against the bill at an earlier stage and were expelled from the Fine Gael party because Prime Minister Enda Kenny has not allowed a free vote on the matter.