Table 1.

Graduated embryo scoring (GES) of cleavage stage embryos

Evaluation	Hours after insemination	Developmental milestone	Score
1	16–18	Nucleoli aligned along pronuclear axis	20
2	25–27	Cleavage regular and symmetrical Fragmentationa	30
		Absent	30
		<20%	25
		>20%	0
3	64–67	Cell number and gradeb 7CI, 8CI, 8CII, 9CI	20
		7CII, 9CII, 10CI, 11CI, Compacting I	10
Total score			100

Fisch. Graduated embryo score (GES). Fertil Steril 2003

^aIf the embryo was not cleaved at 25–27 h, grading of fragmentation should occur at the 64–67 h evaluation if the embryo reached the seven-cell stage and had <20% fragmentation

^bGrade I = symmetrical blastomeres and absent fragmentation. Grade II = slightly uneven blastomeres and <20% fragmentation. Grade III = uneven blastomeres and >20% fragmentation. Grade A embryos are seven or more cells with <20% fragmentation