Dame Margaret Sparrow has stepped aside as president of the abortion reform group she has led for 32 years.

Dame Margaret last night handed over leadership of the Abortion Law Reform Association of New Zealand (Alranz) to national secretary Morgan Healey.

The volunteer group - the oldest pro-choice group in the country - promotes the right of women to choose whether they want to have a termination or continue with an unplanned pregnancy.

Dame Margaret, who was president from 1975 to 1980 and again from 1984, said abortion was not just about public health but an issue of human and women's rights.

"Now is the time to strengthen support for decriminalisation and reform of our antiquated law."

She said she was pleased to hand over the presidency to Dr Healey, who would help the group continue its growth.

Dr Healey said today that the abortion reform movement owed a huge debt of gratitude to Dame Margaret.

"Together with Alranz members and everyone who sees reproductive rights as human rights, I aim to pay tribute to that leadership by continuing to build the movement for change."

Dame Margaret, a life member of the Family Planning Association, received the Distinguished Companion of the New Zealand Order of Merit in 2002, and had her title re-designated in 2009 when she accepted the offer to become a dame.