The condition of the endometrium is an important factor which may influence the success or failure in IVF-ET. This study was undertaken for evaluation of the value of endometrial growth as an early predictor for the success of IVF. Ultrasonographic endometrial measurement were performed in 43 IVF cycles that conceived, 101 cycles that did not with an IVF-ET There was no significant difference in the endometrial thickness and the serum concentration of estradiol in the pregnant versus nonpregnant group(10.4 vs. 9.9 mm: 2348 vs. 2017 pg/ml no hCG administration day). No correlation was found between the ultrasound image and serum estradiol levels around the time of hCG administration(r=0.54, p=0.13 no Day 2; r=0.45, p=0.14 no Day 1). The duration of gonadotropin treatment, number of follicles, number of oocytes retrieved, and fertilization rate were not statistically different in the two groups, however, there was a significant difference in the number of embryos in the pregnant versus nonpregnant group)p< 0.05). A higher pregnancy rate and ongoing pregnancy rate occured with an endometrial thickness over 11 mm compared with below 7mm(p< 0.05, p< 0.005). however, no significant differences were noted in the implantation rate and abortion rate among the groups that classified according to their endmetrial thickness. The endometrial growth(${Delta}$) from hCG administration day(DO) to D6 was greater in the women who achieved pregnancy than in the nonpregnant group(p< 0.01). There were no significant differences in serum estradiol levels, implantation rate, pregnancy rate, and abortion rate among the groups that classified according to the pattern of echogenesity of endometrium, however, significantly higher ongoing pregnancy rate was noted in group A, B compared with group C.(p< 0.0001, p< 0.001) These results suggest that there were no ultrasonographically detectable differences in the patterns of endometrial growth and development around the time of hCG administration in patients who conceive versus those that do not in IVF-ET.