Influence of sperm parameters on outcome of subzonal insemination in the case of previous IVF failure. off.

Subzonal insemination (SUZI) has been proposed for patients with sperm male factor infertility, and in cases of in-vitro fertilization (IVF) failures. However despite SUZI, there still remain couples with very low fertilization rates and even with fertilization failures. Since sperm parameters are known to influence the IVF fertilization rate, we investigated the relation between sperm parameters and the SUZI issue in cases of previous IVF failures with normal or subnormal sperm. Twenty-seven couples were included in the study and were split into two groups according to whether they had normal or subnormal sperm. In the first part of the study a randomized prospective trial comparing SUZI to classic IVF insemination was carried out (11 cycles). In the second part, all the oocytes had SUZI (35 cycles). None of the control inseminated oocytes fertilized. Including all the cases, the fertilization rate after SUZI was 29.8% with a pregnancy rate of 15.2% per cycle. We concluded that: (i) SUZI is efficient for achieving fertilization in cases of IVF failures; (ii) the post SUZI fertilization rate is inversely correlated to the percentage of acrosome defects in the semen (P < 0.001); and (iii) when the sperm is normal, the oocyte quality might be responsible for the previous IVF failures. In spite of a good fertilization rate for this indication, it seems that the chance of having a baby is low.