Fertilization and pregnancy after intracytoplasmic microinjection of acrosomeless spermatozoa.

Spermatozoa lacking acrosomes were injected into the cytoplasm of mature human oocytes. In two subsequent cycles, 12 of 28 (43%) oocytes were fertilized, and the ET of the second cycle resulted in a twin pregnancy. This report describes, to the best of our knowledge, the first case of successful fertilization and delivery after using acrosomeless spermatozoa. Our hope is that with increasing experience with microinjection, in the near future, this type of infertility will not remain a serious problem.