SDLP members have been allowed the freedom to vote as they see fit on abortion matters even if it goes against the party's pro-life position.
Around 100 members of the party attended a special conference on Saturday.
A protest was staged outside the Maghera venue by campaigners of the anti-abortion group Precious Life and there were reports of confrontations as delegates entered.
In a one-line statement on Saturday evening, the party said: "The SDLP membership reaffirmed our position as a pro-life party. The conference also supported freedom of conscience voting for elected representatives.”
The party's easing of restrictions comes ahead of Friday's vote in the Republic on the Eighth amendment of the Irish constitution on its strict abortion laws.
The vote means SDLP members are free to voice their opinions on the referendum.
The BBC reports both party leader Colum Eastwood and his deputy Nichola Mallon supported a free vote.