[Separation of spermatozoa using Percoll gradients: value for in vitro fertilization]

Male infertility can be successfully treated by In Vitro Fertilization (IVF) and Embryo Transfer. However in case of oligo asthenospermia it is often difficult to select enough spermatozoa with good motility for the oocytes insemination. To cope with this problem, in 27 IVF cycles, sperm selection was performed by centrifugation on discontinuous Percoll density gradient. This method was demonstrated to be more efficient than swim-up migration to select motile sperm. The cleavage rate (63%) and the pregnancy rate per cycle (22%) were both satisfying. Centrifugation on discontinuous Percoll gradient was also found to be highly efficient for the removal of bacterial contaminants from semen (20 IVF cycles); the cleavage rate (66%) and the pregnancy rate per cycle (35%) were also quite satisfying. It can be concluded that centrifugation on discontinuous Percoll gradient is a useful method for sperm preparation in IVF in case of oligo-asthenospermia and in case of bacterial contamination in semen.