IVF Embryo Grading Calculator

Understand embryo quality grades and success rates for Day 3 and Day 5 embryos

Last updated: December 2024

Enter Embryo Information

ICM becomes the baby

TE becomes the placenta

Common Questions

What does embryo grading mean?

Embryo grading assesses appearance and development stage. Day 5 blastocysts are graded on expansion (1-6) and cell quality (A-C for ICM and trophectoderm). Day 3 embryos are graded on cell number and fragmentation. Grading helps select the best embryos for transfer.

Can lower-graded embryos succeed?

Yes! While higher grades have better statistics, many successful pregnancies result from fair or even poor-graded embryos. Grading is based on appearance only - it cannot detect genetic normalcy. PGT-A testing can identify chromosomally normal embryos regardless of grade.

What is the difference between ICM and trophectoderm?

The Inner Cell Mass (ICM) becomes the baby, while the trophectoderm becomes the placenta. Both are important - ICM quality may slightly correlate with fetal development, while trophectoderm quality may relate to implantation potential.

How much does age affect embryo quality?

Maternal age is the strongest predictor of embryo quality and success. Age primarily affects genetic normalcy rather than morphological grade. Women over 35 have higher rates of chromosomal abnormalities, even in good-looking embryos.

Medical Sources: Gardner & Schoolcraft (1999) - Blastocyst grading system, Capalbo et al. (2014) - Human Reproduction, Irani et al. (2017) - Reproductive BioMedicine Online, ASRM (2018) - Blastocyst culture and transfer guidelines.

Embryo grading is subjective and varies between embryologists and clinics. Success rates are estimates based on published data. Many factors beyond morphological grading affect implantation success, including maternal age, uterine receptivity, and genetic normalcy. Lower-graded embryos can result in healthy pregnancies. Always discuss your specific embryo quality with your fertility team.