A new fertility technique could boost the chances of predicting a successful pregnancy through IVF by as much as 90 per cent.
Biological scientist Professor Ken McNatty is part of a Victoria University of Wellington team behind a "major breakthrough" that can pick winning eggs.
Other research teams around the world have been working towards this but Victoria's team is the first to get there.
By measuring a few key genes in the discarded cells next to IVF fertilised eggs, the team can target the eggs that are most likely to lead to a live birth. At present, fewer than one in 10 IVF fertilisations end in a live birth, but the team's technique looks to boost the success rate of identifying viable eggs to 90 per cent.
The technique eliminates guesswork at a critical juncture by predicting which eggs are most likely to lead to live births. Usually eggs are extracted, fertilised and incubated, but McNatty said choosing which egg should then be implanted in the uterus is a "hit and miss" process.
But research over the past three years by Fertility Associates embryologist and Victoria University PhD student Jozsef Ekart could do away with most of the uncertainty by allowing clinicians to reliably identify the good eggs much earlier in the process.
The secret is in discarded cells, which hold information on the quality of the egg. By studying the communication between discarded cells and the egg, Ekart has identified three genes linked with successful pregnancies. "We think Jozsef's work gives a 60 to 80 per cent probability of picking the right egg, compared with less than 10 per cent when selecting at random," McNatty said.
"It's not the final solution, but it's a major brick in the wall. It's taken us up another notch in the search for genetic markers - going from random to 80 per cent is a huge jump."
The secret weapon - and competitive edge - in the team's arsenal is a method developed by Victoria University's Janet Pitman that measures a range of gene signals in the discarded cells - healthy signals identify the best eggs. If the team can identify the fourth gene, the odds for predicting viable eggs could rise to 90 per cent, which would be the "gold standard" for bringing the technique into the market as a diagnostic tool. They aim to find the fourth gene within a year.
Once the 90 per cent accuracy standard is reached, a test - now being developed - would check for the presence of the genes in eggs retrieved from ovaries, meaning only the best eggs need to be fertilised.
Last year, for the first time, more women became mothers between the ages of 35 and 39 than those aged 20 to 24, latest Statistics NZ figures show.
- Sunday Star Times
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