zona pellucida drilling
Laboratory technique that creates openings in the embryo's outer shell to assist hatching and improve implantation rates.
Full Definition
Zona pellucida drilling, also known as assisted hatching, is an embryological procedure that involves creating small openings or thinning areas in the zona pellucida (the protective outer shell) of embryos before transfer. This technique is performed using laser, chemical, or mechanical methods to facilitate the natural hatching process that must occur for successful implantation. The procedure may be recommended for patients with advanced maternal age, repeated implantation failure, frozen embryo transfers, or embryos with thickened zona pellucida. While intended to improve implantation rates, the technique requires careful consideration as it may also slightly increase the risk of monozygotic twinning and must be performed with precise timing and technique to avoid embryo damage.
Usage
Usage note: Specify method used (laser, chemical, mechanical); often synonymous with assisted hatching.
In Context
- "Zona pellucida drilling was performed using laser technology on both embryos prior to transfer." — Laboratory procedure note
- "Due to the patient's age and previous failed cycles, assisted hatching was recommended." — Treatment recommendation