What is assisted hatching?
Assisted hatching is a technique used in the in vitro fertilization (IVF). It is used to for improving the embryo implantation in the uterus. It is done by making an opening with a microscopic cut so the embryonic cells are able to easily hatch out. There is no pregnancy without the hatching of the embryo. Just before the implantation occurs, the embryo has to hatch out from its outer shell. Some embryo shells are thicker than others which lowers their ability to hatch and that makes it a lot harder to properly implant. The reasons for the thicker shells of the embryos are unknown but it may have something to do with the woman’s age.
The shell lets only one sperm enter and fertilize the egg. When it is fertilized the cleaving of the embryo into a two-cell begins, then there’s the four-cell and so forth. At the moment the early cleavage stage occurs then the assisted hatching on the embryo can be conducted.
Research shows that the oocyte shells produced by women older than 37 are harder and thicker than those produced by younger women. Reports show that even 75% of the embryos could never hatch. The time that the embryo spends in the laboratory can also add to this hardening of the shell because it is not exposed to the natural environment of the fallopian tubes where the natural enzymes are. There were also suggestions that the shells would harden if the embryos were frozen and thawed. In such cases the assisted hatching is very helpful.
Nowadays very often the laser assisted hatching is used as a very safe way to weaken the shell and let the embryo hatch. Laser assisted hatching is according to studies a better method than doing it manually or chemically. It is more precise and fast.