In some circumstances, the technique of assisted hatching may be used to improve the chances of implantation of the embryos. Using micro-manipulation techniques, the “egg shell” (zona pellucida) is breached to encourage the embryo to break free (hatch) and implant into the uterine lining.
AH is normally carried out on Day Three embryos and is performed just prior to the embryo transfer. Due to the nature of the assisted hatching technique, there is potential risk of damage to the embryo at a rate of approximately 1%.
This technique may be particularly helpful in women who are over forty years of age, those whose eggs have notably thickened shells, women having a frozen embryo replacement and women with multiple previous failed IVF/ICSI attempts.