Kiwi mothers older, having fewer kids
Kiwi women are having fewer babies than at any time in history - and we're waiting till later to have them.
Most women who give birth in New Zealand are now aged between 30-34, the most recently analysed data from maternity wards nationwide shows.
The Report on Maternity 2015, just released by the Ministry of Health, shows almost a third of women who gave birth that year were aged 30-34.
Women are more likely to have a baby at this age than they were a decade ago - with 121.4 babies now born per 1000 women - while birth rates for younger women have fallen off steeply.
The birth rate for women under 20 has dropped by a third since 2006, and is now 18.3 babies per 1000 women.
In contrast, the rate for women aged 40 and over had increased by 15 per cent.
The report also found one in three women who gave birth in 2015 had a "normal" birth - that is, a spontaneous vaginal birth without obstetric intervention in labour or birth.
One in four women had a caesarean section, and just over half were emergency C-sections.
While emergency C-section rates had declined slightly in the last decade, the elective C-section rate continued to rise. Almost 12 per cent of all C-sections last year were elective.
More than half of all women are also now identified as overweight or obese when they first see a lead maternity carer.
Women's Health Action maternal health promoter Isis McKay said the report showed by and large, maternity care in New Zealand was good.
She would like to see more investigation into rising intervention rates.
"Is it maternal choice, is it place of birth, is it their lead maternity carer, and I guess ultimately - does it matter? Is it cause of concern?
"I think it would be interesting to look at how our cultural assumptions about birth could drive those outcomes, alongside clinical indicators. I think it's a real complex matrix of what's driving these rates."
Royal Australasian College of Gynaecology and Obstetrics New Zealand committee chair Ian Page said greater interventions could be partly linked to higher obesity rates and the older age of the birth mother.
Both these factors were more likely to cause risk factors including raised blood pressure and diabetes, which can require interventions, he said.
"You might also have a bigger baby and more fat around the pelvis, making natural childbirth more difficult."
While the maternity report looks at intervention rates and the benefits of vaginal birth, it does not take into account the long-term outcomes for mothers or babies when intervention should have been used.
"It's highly complex so you can't get too hung up on the numbers."
Interventions can include epidural, inducing labour or an episiotomy (surgical cut).
Massey University Associate Professor Paul Spoonley said, when compared with the most recent 2016 birth data from Statistics NZ, the figures showed the "fertility rate" - basically, the number of live births by woman - was the lowest in history.
In the 1960s, there were 4.3 births per woman in New Zealand. Now, there are 1.8 births per woman.
"The first thing to look at is delayed fertility, so women who are having children are getting older, and they often have to make a choice between their job and children.
"We know that increasingly, higher-educated women are choosing not to have children."
Ministry for Women chief executive Renee Graham said the rise in the age women are having children is tied to women's increased participation in education and work.
The Ministry for Women is working to improve workplace flexibility for women who are having babies and returning to work.
Although there are signs workplaces are becoming more flexible, Ministry for Women research found fewer roles with higher levels of skill and pay are available part-time.
This led some women to trade down their skills to achieve flexibility. "Employers are potentially missing out on great workers because they aren't advertising jobs as flexible.