Embryo Assisted Hatching
During the IVF process, the egg is fertilized with sperm in the laboratory. As fertilization takes hold, the cells from the resulting embryo begin to divide. In this early stage, the embryo is contained within a protein layer called the zona pellucida. In order to implant in the uterus, the embryo has to “hatch” out of that layer in order to attach to the uterine lining.
As IVF treatments have developed, laboratory researchers found that embryos with a thinner zona pellicuda had more success during the implantation stage (attachment to the uterine lining). In select patients, in order to give the embryo(s) a better chance of implantation, a small hole is made in the zona pellucida to help the embryo(s) “hatch” out of the zona pellicuda. Assisted hatching takes place 3 days after egg retrieval prior to their transfer into the uterus.
Assisted embryonic hatching relies on an acid solution that weakens a spot on the outer protein layer. The embryos are then rinsed off to ensure that no acid solution remains. IVF with assisted embryo hatching is recommended when either the embryos lack the energy to hatch on their own or when the overall prognosis for implantation is poor. Assisted embryonic hatching is useful for women with advanced age, previous unsuccessful IVF cycles, and when the embryo quality is weak.
Assisting hatching is safe and effective and does not damage the embryos. The procedure does include an increased chance of identical twins.