Recombinant HCG for triggering ovulation increases the rate of mature oocytes in women treated for ICSI

To conduct a prospective randomized study in order to investigate the effect of recombinant HCG (rHCG) on oocyte nuclear and cytoplasm maturity compared to urinary HCG (uHCG), for inducing ovulation in women treated with ICSI for male factor infertility. We compared 89 patients randomly assigned to one of the two study groups. Group A consisted of 42 women who received a subcutaneous (s.c.) injection of 250 mu g rHCG and group B consisted of 47 patients receiving an intramuscular (i.m.) injection of 10,000 IU uHCG. Patients treated with rHCG showed a rate of metaphase II oocytes, a number of metaphase II oocytes with mature cytoplasm and a rate of metaphase II oocytes with mature cytoplasm calculated from total MII oocytes statistically higher than in patients treated with uHCG. However this differences were not associated with a significantly better clinical outcome. Our data show that in women treated with ICSI for male factor infertility, rHCG increases the rate of metaphase II oocytes, the number and the rate of MII oocytes with mature cytoplasm compared to uHCG. A larger study comparing transfer cycles of embryos all derived from oocytes with mature cytoplasm and transfer cycles of embryos all derived from oocytes with immature cytoplasm may be needed to clarify clinical correlations.