Assisted Hatching

To help the embryos implant to the uterus, the “zona pellusida” surrounding the embryo is thinned or ruptured. This procedure is called assisted hatching.

Before fertilisation with the sperm, the egg cell is surrounded by a protective membrane. This membrane protects the embryo from the fertilization stage onwards and acts as a selective barrier between and the embryo and its external environment. On the 5th day of its development, the embryo’s journey that had begun in the fallopian tubes ends in the uterus. At this stage, the embryo needs to hold on to the most suitable place in the mother’s womb. To successfully achieve pregnancy, the “zona pellusida” needs to be ruptured so that the embryo can leave this membrane and implant to the uterus. Sometimes, the membrane surrounding the embryo may be thicker than expected. In these cases, the membrane is thinned through the assisted hatching procedure in order to help achieve pregnancy.

Assisted hatching is usually performed on the day of the transfer. The process can be performed manually under the microscope, or the membrane can be thinned/ruptured using chemicals or a laser beam. Nowadays, the laser method is preferred because it is easier to perform, and because it does not damage the embryo.

• Assisted hatching is recommended in the following cases:

  • In patients over the age of 37,
  • In FET (Frozen Embryo Transfer) cycles,
  • In embryos intended to be transferred and whose membrane thickness is over 15 µm
  • When necessary, in patients with recurrent implantation failures despite the transfer of healthy embryos

  Assisted hatching is not an “on-demand” service, and it does not necessarily have to be performed on every embryo. Your doctor or the embryologists perform this method to selected embryos prior to embryo transfer when necessary, to increase the chance of pregnancy.