The Family Planning Association (FPA) in Northern Ireland goes to the High Court in Belfast today in an attempt to widen the availability of abortion in the North.
The FPA is appealing the outcome of a judicial review last year when it failed in its request for guidelines to be published on the circumstances in which abortions can be carried out in Northern Ireland.
Abortion can be carried out in the North if there is a risk to the mental or physical health of the mother.
Pro-life groups such as Precious Life, Life, Care and the Society for the Protection of the Unborn Child, oppose the liberalisation of abortion laws in the North. Members of these groups are expected to demonstrate outside the High Court today.
Mr Justice Kerr in rejecting the FPA case for clarity on abortion said the legal principles were "clear and easily absorbed". If it was difficult to decide whether a case fell within them, it was not due to lack of clarity.
"Rather this reflects the fact that a value judgment of some subtlety and complexity may be required. That judgment must be made by the clinician who is responsible for the care of the woman . . .," he ruled in a 30-page judgment.
But he also said that while the Department of Health in the North had no legal obligation to provide guidelines, it "will want to consider" whether it would be "a prudent step" to provide them.