Depending on the grade of expansion of blastocyst embryos, we can distinguish between:
- Early blastocyst
- The blastocoel starts to be visible.
- Cavitating blastocyst
- The trophoblast and the inner cell mass can be seen.
- Expanded blastocyst
- The blastocyst has increased in size and the zona pellucida (ZP) becomes thinner.
- Hatching blastocyst
- The blastocyst starts to hatch out of the ZP.
- Hatched blastocyst
- The blastocyst is already completely hatched.
By Alicia Francos Pérez M.D., M.Sc. (gynecologist), Carolina Andrés Santé B.Sc., M.Sc. (embryologist), Cristina Duque Royo M.Sc., Ph.D. (senior clinical embryologist), José Luis de Pablo B.Sc., M.Sc., Ph.D. (senior clinical embryologist), Laura Molina Sotomayor (embryologist), Marta Barranquero Gómez B.Sc., M.Sc. (embryologist), Miguel Angel Checa Vizcaino M.D., Ph.D. (gynecologist), Rebeca Reus BSc, MSc (embryologist) and Cristina Algarra Goosman B.Sc., M.Sc. (psychologist).
Last Update: 05/28/2018