Table 3. Number of cells at D-2 and D-3 for embryos cultured in single medium or sequential media
No. cells No. embryos Single medium (%) No. embryos Sequential media (%) p
D+2 n=486 n=472  
<4 72 (15) 138 (29) <0.001
4 279 (57) 205 (43) <0.001
5 78 (16) 64 (14) NS
6 29 (6) 23 (5) NS
>6 16 (3) 17 (4) NS
Discarded* 25 (5) 12 (4) NS
D+3 n=141 n=145  
<7 29 (20) 53 (37) 0.099
7-8 86 (61) 52 (36) 0.046
9-10 16 (11) 17 (12) NS
>10 5 (4) 10 (7) NS
Discarded* 5 (4) 13 (8) NS
* Embryos blocked or of very bad quality. No: number. NS: not significant.