Embryo morphology score on day 3 is predictive of implantation and live birth rates

To determine if embryo cleavage state or morphology on day 3 correlates with implantation or live birth rates. A retrospective cohort study of all fresh embryo transfers over 2 years.

Patients were grouped by the average cleavage state and morphology. Cleavage state groups were: <6, > or =6, <8, and > or =8 cells. Morphology groups by average grade were: group 1 (best) = 1, group 2 = >1< or =2, group 3 = >2< or =3, and group 4 (worst) = >3< or =4.

The overall implantation rate for 158 cycles was 28.1% with a live birth rate of 37.3%. Morphologic state was highly predictive of both implantation rate and live birth rate. Implantation rates by group were 54.8% (group 1), 30.4% (group 2), 23.8% (group 3), and 11.1% (group 4). Likewise, live birth rates among groups were 61.5, 39, 20, and 21%, respectively. Cleavage state was not predictive of outcome.

Embryo grade is highly predictive of implantation and live birth rate and can be used to determine the number of embryos to transfer. Cleavage state is not predictive of outcome.