Effect of poor motility on pregnancy outcome following intracytoplasmic sperm injection in couples whose male partners have subnormal hypo-osmotic swelling test scores

To determine the confounding effect, if any, of poor motility of sperm that are already compromised by an abnormal hypo-osmotic swelling (HOS) test on pregnancy outcome following in vitro fertilization-embryo transfer (IVF-ET) and intracytoplasmic sperm injection (ICSI). Clinical and live-delivered pregnancy and implantation rates were retrospectively evaluated in first cycles of couples undergoing IVF-ET with ICSI where the HOS test was < 50% according to deciles of subnormal percentage motility (< 50%) and compared to those with normal motility > or = 50%. The combination of very poor motility and low HOS test scores did diminish pregnancy rates following IVF with ICSI. The only part of fertilization of the oocyte that ICSI does not overcome is phase 2 of oocyte activation. Based on these data, the combination of very low percentage motility and low HOS test scores do not adversely affect pregnancy outcome following IVF with ICSI.