Embryos are formed after sperm have fertilized the egg. In an IVF cycle, the new embryos are cultured in incubators for three to five days, and once mature, they are transferred to the uterus, where they must “hatch out” and embed in the uterine lining (endometrium).

Assisted hatching (AH) helps the embryo hatch out of the outer membrane (zona pellucida) by making a small opening in it.  A “hole” is made in the membrane using a chemical (Acid Tyrodes), a microscopic tool, or a laser.  The creation of the opening does not normally damage the embryos.

AH is sometimes recommended for older women, for women who have failed previous IVF cycles, or when the zona pellucida appears thicker than normal.  It is also sometimes employed in cases of unexplained infertility.