Expert urges women in 30s to freeze eggs
Women in their early 30s should start thinking about preserving their fertility by freezing their eggs now, fertility experts say.
Scientists have been able to freeze sperm since the 1950s and the first frozen embryo baby was born in 1993, but egg freezing has been available for less than 10 years.
Gynaecologist William Ledger, of the University of New South Wales, said it was increasingly common for fertile women to delay starting a family, but as they aged they had less chance of conceiving a baby naturally, and were at increased risk of miscarriage or their baby developing conditions like Down syndrome.
Ledger presented data on birth rates from egg freezing at an Australasian medical conference in Adelaide last month.
"A woman of 40 who uses frozen eggs stored from the time she was 30 can expect to have much better perinatal outcomes than attempts at natural conception at the age of 40."
Ledger said he was not suggesting that all women freeze their eggs now, but he believed those in their early 30s who were not planning to have children yet should start considering their options.
The process was not cheap though, usually costing New Zealand women upwards of $10,000 for a single cycle, but should be considered "as a good investment" for those wanting to defer parenthood until later in life.
Christchurch Fertility Associates medical director Dr Greg Phillipson said egg freezing was uncommon in New Zealand and had mostly been used for young women undergoing radiation treatment for cancer, but he agreed that women in their early 30s should consider their options.
"We're not trying to push this service but, on the other hand, I would not talk an informed 34 or 35-year-old out of this."
A woman was born with about 400,000 eggs and lost about 1000 each month.
That rate accelerated after a woman turned 35, meaning many struggled to conceive naturally after reaching their late 30s.
In New Zealand, eggs could only be frozen for 10 years, but could be frozen longer with permission from the Health and Disability Ethics Committee.
The chance of conceiving a baby naturally each month for a woman aged:
30 – 22%
33 – 18%
36 – 13%
39 – 9%
40 - 6%
43 – 2%
46 – < 1%
49 – 0%