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OBSTETRICS AND GYNECOLOGY Reproductive Endocrinology and Infertility

Assisted Hatching of an Embryo

Under normal conditions the embryo undergoes an escape out of its shell (the zona pellucida) before it attaches to the uterine lining and begins to implant. For in-vitro fertilization, an increasing amount of evidence indicates that assisted hatching (AH) should be used selectively for:

  1. Embryos which have shells or coverings thicker than normal
  2. Embryos from patients who have failed multiple IVF cycles.

AH may help to overcome a poor natural mechanism in breaking through the egg's shell, which can become more resistant with age. Assisted hatching consists of creating a slit or hole, either mechanically or chemically, in the shell of the embryo to aid the embryo in its escape of this covering.

Research with antibodies has shown that if the embryo is not able to hatch during the appropriate implantation window, it cannot implant and therefore lead to a pregnancy.

Assisted Hatching of an Embryo