Assisted hatching (AH)
Right up to the time of implantation in the uterus, the early embryo is surrounded by a shell called zona pellucida. The embryo then leaves its shell by hatching. This is an important step towards the implantation of the embryo in the uterus. If the embryo fails to leave the zona pellucida, pregnancy cannot occur.
There are indications that in some cases, the embryos resulting from IVF/ICSI have a thickened or hardened zona pellucida, making it more difficult or even impossible for the embryos to hatch.
In assisted hatching, the zona pellucida is thinned or perforated locally using a special, high-precision diode laser system in order to facilitate hatching.
Improved pregnancy rates by assisted hatching have been observed particularly in patients with several previous unsuccessful embryo transfers as well as in patients above the age of 38 and if cryopreserved oocytes are thawed and transferred (cryo-embryo transfer).
Although no specific risks for the children conceived by this method have been reported and injuring the embryo by assisted hatching is extremely unlikely, it is not possible to exclude any hitherto unknown risks for the children.