Intracytoplasmic sperm injection does not require special treatment of the spermatozoa

In order to assess whether specific treatment of spermatozoa is required prior to intracytoplasmic sperm injection (ICSI), three methods of sperm preparation were compared in this study. These three methods were (A) incubation of spermatozoa with pentoxifylline (PTX) and 2-deoxyadenosine (DOA), (B) electroporation followed by incubation in medium with PTX, and (C) no further treatment with the Percoll gradient. Controlled comparisons were carried out between method A and method B in 21 patients, and between method A and method C in 32 patients. There was no difference in the rates of fertilization and embryo cleavage when ICSI was done with spermatozoa treated by procedures A, B or C. Furthermore, the sperm selection procedure prior to ICSI was done in two different media: T6 medium containing 1.78 mM CaCl2.2H2O and a final washing step after the Percoll gradient in T6 medium containing 5.0 mM CaCl2.2H2O, and Earle's medium containing 1.78 mM CaCl2.2H2O. The results of ICSI on sibling oocytes from 12 patients revealed no difference in the fertilization and embryo cleavage rates between the two different media used during the sperm selection procedures. In conclusion, it appears that high fertilization and pregnancy rates can be obtained in couples with severe male-factor infertility by ICSI and that no special treatment of the spermatozoa prior to ICSI is required.