Table 1: Embryo Morphology (Gardner et al., 2000; Gardner & Schoolcraft, 1999)
Inner Cell Mass quality [the first letter]
A	Well-defined clump of cells
B	Less well-defined and possibly with grainy appearance
C	Few dark cells or possibly no visible mass
Trophoblast [the second letter]
A	Many smooth cells of equal size forming a neat layer
B	Irregular cell layer with some grainy cells
C	Very irregular cell layer with few cells