Low plasma levels of hCG after 10,000-IU hCG injection do not reduce the number or maturation of oocytes recovered in patients undergoing assisted reproduction

Abstract

Purpose: Our purpose was to determine whether there is a correlation between human chorionic gonadotropin (hCG) blood levels and oocyte maturation. Methods: Three samples of blood were obtained at different times from hCG administration as follows: 12 hr, 36 hr, during oocyte recovery, and at 84 hr, when the patient comes for embryo transfer. Results: A total of 5036 oocytes was retrieved from 404 patients prospectively recruited between April 1996 and March 1997. The percentage of metaphase-II oocytes at different blood levels ranged from 84 to 88%. The general trend does not show any significant increase in percentage of metaphase-II oocytes in association with an increasing serum hCG concentration. Conclusions: The results of this study suggest that at 12, 36, and 84 hr after hCG administration, levels as low as 50, 45, and 9 IU/L of hCG, respectively, are equally potent as higher levels at initiating maximal oocyte maturity.