The European Court of Human Rights has ruled that Ireland has failed to properly implement the constitutional right to abortion where a woman is entitled to one where her life is at risk.

The ruling will put the issue of abortion back on the political agenda and is likely to force the Government to introduce legislation or official guidelines on access to abortion for women whose lives are at risk.

In a statement this evening, the Government said it “will examine the judgement carefully and consider what steps are required to implement the judgment”.

Taoiseach Brian Cowen said the ruling raised “difficult issues” that needed to be carefully considered. Speaking in Brussels, he said it was much too early to make any decision on whether legislation would be required in light of the court’s decision.

Minister for Health Mary Harney said the Government would take legal advice. Acknowledging the judgment was binding on the State, she said the Government would have to come forward with proposals to reflect it. “However, this will take time as it is a highly sensitive and complex area,” Ms Harney said.

The court unanimously ruled this morning that the rights of one of three women who took a case challenging Irish abortion laws were breached because she had no “effective or accessible procedure” to establish her right to a lawful abortion.

The woman – known only as “C” – had a rare form of cancer and feared it would relapse when she became unintentionally pregnant.

However, the woman was unable to find a doctor willing to make a determination as to whether her life would be at risk if she continued to term.

This morning, the court concluded that neither the “medical consultation nor litigation options” relied on by the Government constituted an effective or accessible procedures.

“Moreover, there was no explanation why the existing constitution right had not been implemented to date,” the court ruled.

“Consequently, the court concluded that Ireland had breached the third applicant’s – "C" – right to respect for her private life given the failure to implement the existing constitutional right to a lawful abortion in Ireland.”

The court ruled that there had been no violation of the rights of the two other women involved in the case - "A" and "B".

The Strasbourg-based court, which is separate from the EU, adjudicates on human rights issues among all 47 member states of the Council of Europe

The identities of the women, who took the case, remain confidential.

Two of them are Irish and one is a Lithuanian national who was residing in Ireland. All of them travelled to the UK to have an abortion after becoming pregnant unintentionally.

They include a woman who ran the risk of an ectopic pregnancy, where the foetus develops outside the womb; a woman who received chemotherapy for cancer and was unable to get clear advice on the dangers posed by an unplanned pregnancy; and a former alcoholic and drug abuser who feared her unplanned pregnancy would jeopardise her attempts to be reunited with her other children in the care system.

The women - supported by the Irish Family Planning Association - argued before the court last December that they were subject to indignity, stigma and ill-health as a result of being forced to travel abroad for their abortions.

The Government robustly defended the laws and said Ireland's abortion laws were based on “profound moral values deeply embedded in Irish society”.

It argued that European Court on Human Rights has consistently recognised the traditions of different countries regarding the rights of unborn children. However, it maintained that the women’s challenge sought to undermine these principles and align Ireland with countries with more liberal abortion laws.

The case was lodged before the court in 2005 and was heard last year at an oral hearing before the European Court of Human Rights's grand chamber.

This 17-judge court is reserved to hear cases that raise serious questions affecting the interpretation of the European Convention of Human Rights.

As a signatory to the European Convention on Human Rights – now incorporated into Irish law – the Government is obliged to remedy any breaches of the convention.