Police Minister Judith Collins has pledged to support a call for laws to prevent girls under 16 having abortions without their parents being told.

Collins said she would support a private member's bill requiring parents to be involved before a termination could take place.

She could not introduce it herself, because ministers can only introduce legislation related to their own portfolios, but her stand comes after the Sunday Star-Times revealed a mother's anger that a school counsellor arranged an abortion for her teenage daughter.

While in opposition in 2004, Collins proposed the Care of Children Act be amended to make parental notification mandatory for girls under 16. The act allows a female of any age to consent to an abortion. Collins proposed that if a girl objected to parental notification, a doctor would contact the district court to arrange an appointment for the girl to see a judge in chambers within 24 hours.

Finance Minister Bill English supported the amendment. "If a school doctor wants to give a pupil a Panadol, they have to tell parents ... It is time to swing the pendulum back in favour of parents," he said then. "Where there are significant events affecting children, and real risks to their welfare, parents should be involved.

"The idea that the law allows your 12 to 14-year-old daughter to have an abortion on her own and go back to school is repugnant."

But the move was opposed by the College of General Practitioners and the Medical Council and was lost when it was voted on.

Collins said she was aware there was interest among some National backbenchers in putting forward an amendment again, but any private bill would have to be drawn from the ballot on members' day before it could be introduced.

In 2004, Collins argued that suggestions her approach would see more terminations, and a rise in illegal backstreet abortions, was "just plain scaremongering".

"We constantly tell parents they should be more responsible for their children.

"But if they don't have all the information, what can they do?"

In places where parental notification was mandatory, teenage abortions and pregnancies actually fell, she added. "No child should go through the trauma of abortion on their own."

Backbench National MP Paul Hutchison, a former National Women's Hospital obstetrics and gynaecology consultant, said debate on reproductive health was essential.

"That should come before this issue. We have to tread lightly, doing everything possible to have the parents involved. But having worked in places like National Women's, where I saw women who had been beaten by their families because of an unknown pregnancy, that's why the law is there," he said.

"It's a delicate balance. The onus should be on the counsellors doing everything to influence the women to be prepared to have their parents involved," he said.

In 2009, 3950 girls aged 11 to 19 had abortions.