Are frozen embryos healthier than fresh embryos?
IVF babies which developed from frozen embryos are much healthier compared to those which developed from fresh embryos. This is according to three different studies in three different countries in three continents, as reported by several news dailies, including the British paper The Herald.
A Finnish study observed that babies from fresh embryos have 35% and 64% higher likelihood to be premature and have low birth weight, respectively compared to babies from frozen embryos.
Study # 2:
A US study did a similar comparison and found that babies from frozen embryos are 51% more likely to have low birth weight and 15% more likely to die.
Study # 3:
A similar comparative study in Australia gave the following results:
- Low birth weight – 11% (fresh embryos) vs 6.5% (frozen embryos)
- Prematurity – 12.3% vs. 9.4%
- Mortality – 1.9% vs. 1.2%
All three studies were presented at the 64th American Society for Reproductive Medicine conference in San Francisco which runs from November 8 to 12.
The reason why frozen embryos produce fitter and healthier babies is not so clear. However, it is known that the success rate of IVF using frozen embryos is much lower than success rate using fresh embryos. It may be possible that the unhealthy frozen embryos do not survive beyond the implantation stage, leaving the fittest and the healthiest to survive with good outcomes. Other experts believe that there may be subtle biological reasons that are not yet fully known.
In any case, these developments are of particular interest for people who are considering to undergo IVF.