Human fertilization by micro-injection of immotile spermatozoa

Microfertilization of human oocytes with spermatozoa from a man with immotile cilia syndrome is reported, confirming a preliminary investigation where a zona-free donor oocyte was fertilized with spermatozoa from the same patient. Oocytes from his spouse were obtained by laparoscopy after routine stimulation with clomiphene citrate, human menopausal and chorionic gonadotrophins, and were cultured for 4-6 h in Whittingham's T6 medium, supplemented with 10% of her serum. The spermatozoa were washed and processed in the same medium and capacitated for 6-8 h before micromanipulation. Three of five mature oocytes were fertilized by micro-injection of a single immotile spermatozoon into the perivitelline space. One oocyte produced a two-pronuclear ovum assessed 19 h after injection, while the other two produced 2-cell embryos with blastomeres of equal size, 22 h after injection. These embryos cleaved to 3-8-cell stages in culture before embryo replacement. No pregnancy resulted from embryo transfer. The results conclusively demonstrate that human oocytes can be fertilized successfully with immotile spermatozoa by micro-injection and the work has profound implications in the treatment of severe male infertility.