Mick Wallace's Bill on terminations in cases of fatal foetal abnormalities has been rejected by the Dáil.
It was defeated by 95 votes to 45 votes.
The legislation proposed permitting terminations when babies are not expected to survive.
The Taoiseach had effectively given the Independent members of the Cabinet a free vote on the Bill, which had been brought forward by Wexford TD Mick Wallace.
A number of members of the Independent Alliance had insisted they would vote in favour of allowing terminations in the cases of fatal foetal abnormality.
Shane Ross and junior ministers Finian McGrath and John Halligan all supported the bill, contrary to Government advice.
There they go. Ross, Halligan and McGrath vote in favour of Wallace FFA Bill, against govt advice #Dáil
— Gavan Reilly (@gavreilly) July 7, 2016
Fianna Fáil had been granted a free vote, but only five of its 43 TDs supported the bill.
The Attorney General had told the Government that the legislation was unconstitutional.
Earlier, Deputy Wallace told Pat Kenny that there had been "a bit of confusion" about his Bill.
He explained: "We're not talking about life-limiting illness [...] We are talking solely about situations where the prospects are fatal - and where fatal is not open for question."