The purpose of this study was to evaluate the applicability of continuing daily injectable GnRHa, after pituitary desensitization, for the first 4 or 5 days of ovarian stimulation. We proposed a new calculation and estimated that it took as early as 6 to 7 days for pituitary and gonadotropin release to return after cessation of daily administered leuprolide acetate. A modified regimen based on this new calculation, i.e. Daily administered GnRHa continued for the first 4 or 5 days with ovarian stimulation after pituitary desensitization had been achieved was applied to patients undergoing assisted reproductive technology (ART). Thirty-five patients prospectively assigned to use this early discontinuation regimen were analyzed with respect to age, indications, duration of ovarian stimulation, dose of exogenous gonadotropin required, ovarian response and oocytes obtained, rate of fertilization, and rates of pregnancy. There was no spontaneous LH surge occurred. Premature luteinization occurred in one patient. We concluded that, after pituitary desensitization, there was no spontaneous LH surge when daily administered GnRHa continued for 4 or 5 days only with ovarian stimulation. Impacts on the ART outcome required further evaluation in a prospectively randomized study. Based on theoretical estimation, cessation of GnRHa at the beginning of ovarian stimulation might eliminate most, but not all, spontaneous LH surges.