Laser Assisted Hatching (LAH)

Pregnancy cannot occur unless the embryo implants itself in the uterine wall, and this cannot happen until the embryo has hatched. In laser assisted hatching, a precision laser is used to facilitate the hatching process by incrementally removing the zona pellucida—the membrane encasing the embryo——prior to transfer.  This method is especially recommended in cases of frozen embryo transfer (FET), as the process of freezing makes the cover of embryos harder to breach. The laser is highly precise and causes no damage to the embryo; it also avoids the cons of mechanical and chemical-based forms of assisted hatching, which require more physical handling. Laser assisted hatching is faster than other methods, as well, meaning the embryo spends less time outside the incubator. The procedure is typically performed on day four or five following fertilisation, when the embryos are naturally more inclined to hatch.