Laser Assisted Hatching (LAH)
For implantation to successfully occur, an embryo must first hatch, but sometimes a little help is needed—especially in the case of frozen embryo transfer (FET). Laser assisted hatching (LAH) provides the necessary assistance by separating the outer shell (‘zona pellucida’) from the blastocyst in increments, using a precision laser. The procedure is not harmful to the embryo and avoids the shortcomings of alternative mechanical and chemical forms of assisted hatching. It is also faster than these, which means the delicate embryo experiences less time outside its incubator. LAH is usually carried out on the fourth or fifth day of embryo culture.