Embryology
Before implanting, a blastocyst must escape the zona pellucida. An embryo seen beginning this process is described as hatching, and is often at an advanced stage of expansion. It is a normal developmental step rather than a special quality marker.
Also known as: hatched blastocyst, hatching
Sources
- European Society of Human Reproduction and Embryology (eshre.eu)
- Royal Australian and New Zealand College of Obstetricians and Gynaecologists (ranzcog.edu.au)
Last reviewed: 10 September 2026. Written by the Antega Editorial Team. General information only — always follow the advice of your own clinic, doctor or pharmacist.