Table 2. Embryo quality according to the ASEBIR guidelines on D-2 and D-3 for embryos cultured in single medium or sequential media
Class No. embryos Single medium (%) No. embryos Sequential media (%) P
D+2 n=486 n=472  
A 190 (39) 107 (23) <0.001
B 133 (27) 118 (25) 0.018
C 154 (32) 215 (45) NS
D 9 (2) 32 (7) 0.012
D+3 n=141 n=145  
A 40 (28) 19 (13) 0.048
B 40 (28) 49 (34) NS
C 47 (34) 59 (41) NS
D 14 (10) 18 (12) NS
No: number. NS: not significant.