Oocyte like every other cell has a fatty-protein shell (zona pellucida) which later protects small embryonic cells falling apart. In the in vitro environment, there is a possibility that zona pellucida hardening more than usual, especially with embryo freezing. Sometimes its thicker than usual naturally. Hardened or thick zona pellucida does not let the blastocyst hatch out and engage to implantation process.
Assisted Hatching is a procedure to drill a slit/gap on the zona pellucida. With the slit/gap on the “shell”, it is easier for a blastocyst to hatch out. At Harvest Fertility, embryologists will use a safe laser beam through a micromanipulator microscopic system to focus on the zona pellucida and make a slit/gap on it.