IGF-1 n = 76) were used to determine total cell number. A total of 4 replicates were

completed.

Statistical Analysis

 Data were analyzed by analysis of variance using the GLM procedure of SAS

(SAS for Windows, version 9.0, SAS Inst., Inc., Cary, NC). Percentage data were

transformed by arcsin transformation before analysis. Independent variable for the

following variables were IGF-1 treatment and replicate: cleavage rate, blastocyst

development, total cell number, percent apoptosis, the number of ICM and TE cells, and

the ratio of TE cells to ICM cells. For gene transcripts, treatment was the only

independent variable included in the model. All values reported are least-squares means

+ SEM. Probability values for percentage data are based on analysis of arcsin-

transformed data while least-squares means are from analysis of untransformed data.

 Results

 Among grade 1 expanded blastocysts selected on d 7 after fertilization, treatment

with IGF-1did not affect total cell number or the proportion of blastomeres that were

apoptotic (Table 2). There was also no effect of IGF-1 treatment on the number of cells

in the TE or the ratio of TE:ICM. There was, however, a tendency (P < 0.06) for IGF-1

treated embryos to have less cells in the ICM than controls (Table 2-2).

 Results on relative abundance of the 14 gene transcripts are presented in Figure 1.

Among transcripts involved in cell to cell adhesion and blastocyst expansion, treatment

with IGF-1 tended (P < 0.08) to increase relative abundance of NaK transcripts and

increased (P < 0.01) relative abundance of Dc II transcripts. There was no effect of IGF-

1 on relative abundance of transcripts for Ecad or Plako. Of the two genes examined that

are involved in apoptosis, IGF-1 tended to increase (P < 0.06) relative abundance of Bax