Assisted Hatching IVF for Improved Implantation Rates

happy couple looking at pregnancy test

In vitro fertilization (IVF) failure is a frustrating experience for individuals and couples, and it is often caused by an embryo’s failure to implant in the uterus.

If you’ve had more than one failed IVF cycle or have a poor prognosis for IVF, your fertility doctor may recommend a technique known as assisted hatching.

What is assisted hatching?

After an egg is fertilized in the laboratory, the cells begin to divide. During these initial stages of development, the embryo is contained in a layer of proteins known as the zona pellicuda. In order to successfully implant into the uterine lining, an embryo has to hatch out of the zona pellucida and attach to the walls of the uterus.

Assisted hatching is a newer lab technique that was developed when fertility experts observed that embryos with a thin zona pellucida had a higher rate of implantation during IVF. With assisted hatching, an embryologist uses micromanipulation under a microscope to create a small hole in the zona pellucida. This happens on the third day of embryo development when the embryos contain an average of six to eight cells.

The embryos are stabilized by a holding pipette. On the opposite side, a small laser creates a small defect in the zona pellucida. The embryos are then returned to the incubator for further development.

Who should use assisted hatching with IVF?

Assisted hatching is thought to be helpful for some couples with a poor prognosis whose embryos are thought to lack sufficient energy to complete the hatching process.

According to the American Society for Reproductive Medicine, assisted hatching may be indicated for women with:

  • advanced maternal age (older than 38)
  • two or more failed IVF cycles
  • poor embryo quality

Will assisted hatching increase the chances of IVF success?

Assisted hatching has been found to improve clinical pregnancy rate in poor prognosis patients.

But since assisted hatching is a difficult technique, the success is dependent on the embryologist’s experience and technique. It is important to talk with your fertility clinic about how successful they are with the procedure.

Is assisted hatching with IVF safe?

There can be complications from assisted hatching. It may be associated with damage to the embryo and damage to individual blastomeres, with a reduction in the viability of the embryo. In addition, assisted hatching has been associated with an increased risk of twin pregnancy.


Dr. Taraneh Gharib Nazem is Senior Fellow in Reproductive Endocrinology and Infertility at the Icahn School of Medicine at Mount Sinai/Reproductive Medicine Associates of New York. She is a board-certified Obstetrician Gynecologist. Dr. Nazem completed her residency in Obstetrics and Gynecology at the New York University School of Medicine, where she was elected administrative chief resident and graduated with the Robert F. Porges Honor Resident Award, for outstanding performance.