Where the parties stand on the Eighth
Taoiseach Leo Varadkar may be backing proposals that would allow unrestricted abortion up to 12 weeks if the referendum passes, but he can't yet say a majority of Fine Gael's 50 TDs support the plan.
Twenty-one have publicly expressed their support for such legislation, but 11 are against and 18 remain undeclared. The party has a free vote on abortion issues and there is a majority supporting repeal of the Eighth Amendment with 31 in favour, six against and 13 undeclared.
Fianna Fáil also has a free vote but despite leader Micheál Martin backing the 12-week proposal, 34 of the party's 45 TDs are against it with just eight in favour.
Sinn Féin does not currently support abortion without restriction.
Twenty-one of the party's 23 TDs favour repeal and Sinn Féin has indicated it will hold a special ard fheis to consider the 12-week issue.
All Labour, Green Party, Social Democrats and Solidarity-People Before Profit TDs support both repeal and 12 weeks.
The Independent Alliance is split on both issues and the views of other Independents range from the strongly pro-choice minister Katherine Zappone to the ardently pro-life Tipperary TD Mattie McGrath.