A National Party list MP supports the right of parents to choose whether or not to vaccinate their children.
The MP, Maureen Pugh, said she respected parents' rights to choose not to vaccinate their own children, even if that endangered others.
The government has a goal of ensuring 95 percent of all eight-month-old children are immunised.
It said it was difficult to protect the wider community unless there were very high immunisation rates.
But Mrs Pugh told reporters at Parliament while her own children were immunised, she supported the right of other parents not to.
"I agree that they have the right to make their own choices," she said.
Mrs Pugh said she knew not vaccinating children could endanger others but she still thought parents should be able to choose.
"People have made their own choices about these things and I respect their right to do that," Mrs Pugh said.