Laser Assisted Hatching Or What is hatching?

A embryo has a soft outer ‘shell’ called the zona pellucida (or zona for short). When an embryo is five or six days old and is at the stage known as a blastocyst, it needs to escape or hatch out of the zona. Once the embryo has hatched out of the zona, it is able to implant into the lining of the womb and a pregnancy results. If the embryo does not hatch a pregnancy cannot occur.

What is laser assisted hatching and how is it done?
Laser assisted hatching is a technique whereby a small artificial hole is made in the zona of an embryo using a laser. It is thought that the embryo can then hatch more easily through this hole and hopefully increase the chance of the embryo implanting.

Laser assisted hatching is performed just before the embryo transfer procedure and can be performed on embryos at the early cleavage stages (that is two or three days after the egg collection) and at the blastocyst stage (five or six days after the egg collection).

Who should be treated with assisted hatching?

We would recommend assisted hatching in patients who meet one or more of the following
criteria but will also consider requests from patients outwith these criteria on a case-by-case
basis.
• Repeated implantation failure (at least two previous transfers)
• Patients with a lower chance of implantation (AMH < 7.0 pmol/l, irrespective of age)
• Patients 37 years and older
• Patients undergoing frozen embryo transfer
• Embryos with a thickened zona pellucida


Safety of assisted hatching :
Because it is an incomplete breach of the zona pellucida, there is no risk to the embryo and reassuringly, all the data to date shows that assisted hatching is safe for embryos and does not increase the risk of physical or chromosomal abnormalities in the baby.