Before an embryo can attach to the wall of the womb, it has to break out or ‘hatch’ from its outer layer called the zona pellucida.
It has been suggested that making a hole in or thinning this outer layer may help embryos to ‘hatch’, increasing the chances of the woman becoming pregnant in some cases.
Assisted hatching is done while the embryo is in the laboratory.
Before being transferred back to the womb a hole is made in the outer layer of the embryo or it is thinned, using acid, laser or mechanical methods.
Some clinicians believe that the use of Assisted Hatching results in higher pregnancy rates in selected cases. For example, it has been noted that in the older woman the zona pellucida around the embryo can appear to be thickened. The making of a ‘weak point’ in the zona may help implantation.
Current research suggests that this treatment is no more likely to cause an abnormality to the baby than IVF without Assisted Hatching. As it is only the outer layer that is affected by this procedure, the embryo should remain unharmed.