Assisted Hatching (AHA)
Sometimes the proteins in the zona pellucida may malfunction, which makes it difficult for the embryo to attach to the uterus. This may prevent the embryo within the zona pellucida from hatching and attaching to the uterus. In assisted hatching, a small incision is made in the zona pellucida on the day of embryo transfer to assist the embryo in hatching, either using a special pipette, an acid solution, or laser technology. Abnormalities in the protein structure cannot be seen microscopically, and a clinical examination method is not available for routine use. Assisted hatching is used upon discretion in cases where no particular reason for repeated treatment failures cannot be found or if the zona pellucida is thicker than usual.