Abortion in New Zealand will keep its present form and functions following a decision released on Thursday by the country's Supreme Court, which upheld an earlier ruling that says assessments handed down by abortion consultants cannot be reviewed by the Abortion Supervisory Committee.

The scope of responsibilities bestowed by NZ's abortion laws to the statutory body do not include poring over on each cases of legal pregnancy termination, the Supreme Court said, sustaining the position taken by the country's Court of Appeal on the matter.

The appeals court previously overturned a High Court move in 2011 that allowed the abortion committee to check on decisions made by certifying consultants, two clearances from which must be secured by NZ applicants wishing to legally abort their pregnancies.

The Supreme Court has agreed with the Court of Appeal that the earlier decision from the High Court will not stand on any legal precepts or at least on present laws that support New Zealand's abortion policy.

In handing down its decision, the country's highest court also rejected the arguments lodged by Right to Life New Zealand, which has been fighting for the abortion committee to look deeper on cases being handled by certifying consultants.

The pro-life advocacy group has been calling attention on the likelihood that many incidents of legal abortion in New Zealand may have been performed beyond the bounds of the country's existing laws on the subject.

It would be prudent on the part of legal authorities to place safeguards that would ensure the abortion laws were not being abused, the group said, adding that review by the legal body on decisions by consultants would be a good start.

But the Supreme Court is convinced at this time that NZ laws do not provide for such specific functions by the abortion committee, noting too that the supervisory body has yet to fully realised "the breadth of its functions and powers."

Within its present make-up, the Supreme Court also suggested that the committee could launch initiatives that would clarify the general methods employed by consultants in dealing with abortion applications brought before them.

But such reviews can only be conducted "after any authorised termination had taken place to determine if they were consistent with legislation," according to reports by Fairfax New Zealand.

In ending the legal arguments on the issue, which according to the Australian Associated Press (AAP) was first pursued by Right to Life in 2005, the Supreme Court has encouraged the committee and the NZ parliament to pick up and probe on claims that the country's abortion laws were being employed far from their original designs.