"We want caesareans performed on the basis of clinical indicators rather than personal choice, which is in line with best practice in New Zealand and Australia.
"We've given women a choice in the past.
"There's still choice there. No one's saying definitely not, but there will be negotiating. We want to provide sound and appropriate clinical care, and follow best practice."
Although caesarean sections were more expensive than natural births, the financial implications had not been a part of the discussion to reduce caesarean rates, said Mr Bos.
Wairarapa Hospital obstetrician David Cook said a natural birth was considered to be the safest way to give birth, despite caesareans being safe.
Dr Cook said there were risks with both, and it was important to measure the risks of caesareans but difficult to measure the long-term impacts of natural birth to provide comparison.
"It's a debatable point - how good is a natural birth for a woman's body in the long run?"
A natural birth was still ideal, said Dr Cook, and most women chose it if they could.
"A handful of caesareans are people who just requested it, but most people, when you explain carefully the ins and outs they're willing to give [natural birth] a go."
Masterton Medical GP obstetrician Simon Prior said caesareans were almost always done to ensure a healthy baby, and were done in consultation with specialists and parents.
He said caesarean sections were often decided on during labour, if the baby was showing signs of distress or the labour had been very poor despite best efforts. "Often a decision to have a caesarean is a big relief to everybody, including to the woman who is often exhausted, and we don't want the baby suffering."
Few women insisted on a caesarean as a personal choice, though many second-time mothers - who would not be counted in the maternity indicators - who had caesareans the first time might opt to.
