Table 1.

Comparisons of clinical characteristics among groups divided by serum estrogen levels on the endometrium transformation day.

Groups	Age (years)	Endometrial thickness on the transformation day (mm)	Endometrial thickness on the blastocyst transfer day (mm)	Days of taking progynova	P level on the blastocyst transfer day (ng/ml)	Number of high-quality blastocysts transferred
A1 (n = 176)	30.16 ± 3.42	9.89 ± 1.43	10.66 ± 1.61	13.25 ± 1.70	15.09 ± 5.74	1.88 ± 0.41
A2 (n = 178)	30.10 ± 3.16	10.02 ± 1.49	10.45 ± 1.75	13.51 ± 1.85	14.85 ± 6.96	1.81 ± 0.50
A3 (n = 176)	30.78 ± 3.41	9.74 ± 1.44	10.45 ± 1.97	13.76 ± 2.13	14.67 ± 6.58	1.80 ± 0.48
A4 (n = 178)	30.33 ± 3.54	9.89 ± 1.61	10.44 ± 1.69	14.49 ± 2.10	14.12 ± 7.46	1.83 ± 0.46
F	1.477	1.039	0.641	13.268	0.666	3.911
P	0.220	0.375	0.589	0.000	0.573	0.271