The influence of exogenous human chorionic gonadotropin cycles with spontaneous luteinizing hormone surges on the outcome of in vitro fertilization.

Thirty consecutive patients who displayed endogenous luteinizing hormone (LH) surges and reached oocyte recovery for the purpose of in vitro fertilization were reviewed (LH surge group). Another 37 patients receiving human chorionic gonadotropin (hCG) in the absence of an LH surge served as a control group (no surge-hCG group). All patients underwent ovulation induction using clomiphene citrate (CC) plus human menopausal gonadotropin (hMG). The numbers of oocytes recovered and embryos transferred were significantly lower in the LH surge group compared with the no surge-hCG group (P less than 0.05). Nevertheless, the pregnancy rate per oocyte recovery between the two groups appeared similar (20 versus 16%). Among the 30 patients with a LH surge, 9 received hCG after a LH surge was verified, whereas the others did not. Addition of hCG to the LH surge increased the numbers of oocytes recovered, embryos transferred, and the pregnancy rate (3 out of 9 versus 3 out of 21); however, this difference is not statistically significant. Furthermore, the addition of exogenous hCG to a spontaneous LH surge appears to be necessary to maximize the number of oocytes recovered, embryos transferred, and pregnancies obtained.