More Kiwi women became mothers between the ages of 35 and 39 last year than those aged 20 to 24, new figures show.
Statistics New Zealand said yesterday that it was the first time the older group had given birth to more babies (71 births per 1000 women) than their younger counterparts (67 per 1000).
Midwifery adviser Lesley Dixon, of the New Zealand College of Midwives, said women were waiting to have children because they had more options than they did 20 or 40 years ago.
"They're often choosing to have a career before becoming a mother. They'll have their own home or are in a committed relationship; generally they're in a more stable part of their life."
According to the college's latest annual report, about 30 per cent of women who gave birth were first-time mothers, meaning most of the women aged 35 to 39 having babies last year would have already had at least one child.
Fertility Associates Christchurch medical director Sarah Wakeman said most of the women she gave fertility treatment to were aged in their late 30s.
The chance of conceiving naturally was about 20 to 25 per cent each month for a woman aged up to 30, but dropped to only 6 per cent by the time she was 40.
Dr Wakeman believed societal changes were the main reason women were having children later, although developments in fertility treatment would have also contributed.
Dr Andrew Murray, of Fertility Associates in Wellington, said there was an increasing public awareness that waiting to have children was risky.
The chances of conceiving started to decline after a woman reached 30 and plummeted steeply after 35. A woman under-30 trying to conceive had around a one in four chance in any given month of succeeding. But by the time they had reached 40, this had dropped to about one in 20.
Having children later also increased the chances of a miscarriage or foetus abnormalities, such as Downs Syndrome, he said.
But despite the chance, he doubted the trend towards older mothers would reverse anytime soon.
"People are more aware, but they just don't think it will happen to them," he said.
THE RIGHT TIME
Hurtling towards middle age, Sue Trueman decided she had no time to find a father for her children.
The Upper Hutt woman instead had her first child just as she turned 40, with the help of a donor. Eight years later she has two children, both by donors.
She is part of a growing trend for Kiwi women to have children later, and it is now more common for new mothers to be in their late 30s than in their early 20s.
Trueman's own mother had her when she was 23, just 18 months after marriage. But her daughter opted to spend her 20s focused on travelling and work, with children always a distant and undecided possibility.
She did not regret having her children later, even though she was left with no time to find a fellow parent.
"I wasn't really interested in having kids till I was 30, and by then I just didn't meet the right person to have kids with.
"I thought 'I can't wait around for the right person to come along any more, my biological clock is ticking'."
Having children at a later age has had its downsides. Their births were probably more difficult and she often felt she lacked the energy to keep up with her young kids.
"And by the time my children have kids, I will be quite old."
However, it also meant she was in a better financial and emotional state to look after her children by herself. By the time she hit her late 30s she had a solid career - she works for Plunket - owned her own house and was ready to settle.
"If you want to have children, and there's no-one around to have children with, go ahead and do it anyway. I love being a mum."
- The Dominion Post
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