Taoiseach Mr Ahern and his coalition colleagues were today assessing the implications of a second referendum defeat in less than a year.
The poll result last night confirmed rejection of the Government's bid to amend the constitutional ban on abortion. The result guarantees the barrier to termination except in cases where the life of the mother is shown to be at risk.
Voters were asked to row back the Supreme Court X case decision, which allows abortion where the mother is shown to be suicidal.
Last June, the Irish electorate turned down the Nice Treaty for EU expansion. The Government's second referendum defeat comes just weeks before Mr Ahern will be obliged to call a General Election.
Recent opinion pointers have suggested Fianna Fáil will at least hold on to its current parliamentary strength. But the latest referendum setback could count against their electoral prospects by damaging morale, according to some political analysts.
Mr Ahern will launch his fightback tonight at the opening of Fianna Fáil's ardfheis in Dublin. He will attempt to put the poll result behind him when he delivers his keynote conference address to the 6,000 delegates tomorrow night.
Pressure is set increase on the government to seek a legislative way out of the abortion impasse created by the referendum vote. Fine Gael and Labour moved swiftly after the poll declaration to make clear that would be their favoured option.
Fine Gael leader Mr Michael Noonan said: "Dealing with this issue through legislation will require leadership, something Mr Ahern has so far singularly failed to provide".
Labour Party leader Mr Ruairí Quinn demanded abortion legislation, saying: "The outcome will mean a more tolerant and compassionate Ireland than would have been the case had the amendment been passed".
PA