By MONIQUE DEVEREUX health reporter
The number of twins and triplets born through fertility treatment in New Zealand is at a record high, and one in five parents can now expect a multiple birth.
The rate mirrors new in-vitro fertilisation (IVF) statistics from Australia. NZ experts say the trend is likely to
continue for at least another two years.
The increase is a result of medical advances and lifestyle changes, which combined have created a higher chance of an IVF pregnancy reaching full term.
The IVF treatment programme involves gathering sperm from the would-be father and eggs from the would-be mother, and combining them in a dish in an incubator.
Embryos are monitored and later selected by specialists for placement inside a woman's uterus.
For women aged under 37, two embryos are chosen for placement. Women over 37 are more often implanted with three.
The programme is expensive and costs up to $5000 each cycle.
In the past two years, the number of births through IVF has doubled and recipients now have a 35 per cent chance of becoming parents.
The director of Auckland's Fertility Associates, Dr Richard Fisher, said the increase was mainly due to better medical procedures.
Embryos were now cultured in fluid that was much more similar to that inside the uterus. Previously, they grew in a saline solution.
Changing lifestyles had also pushed the birth rate higher, as prospective parents took better care of their own health.
Dr Fisher said the increase in multiple births was a case of the fertility specialists being "caught by our own success."
But the high rate was part of a transitional period and within two or three years, multiple birth rates would start to fall.
He said some "brave" fertility centres overseas had started to replace just one embryo at a time, which kept the multiple-birth rate around the more acceptable 10 per cent level.
"But it will be a while before we can contemplate doing that here. The procedure is not inexpensive, especially if it takes two or three cycles to find the right result."
Around one in six couples needs medical help to conceive.
