A self-migration method for preparation of sperm for in-vitro fertilization.

Human sperm samples (n = 211) were prepared for in-vitro fertilization (IVF) and embryo transfer by a self-migration procedure in Earle's medium containing highly purified hyaluronic acid (Hya) (MW 3,000,000) included to increase the viscosity of the medium. The method resulted in the recovery of a significantly higher percentage of motile spermatozoa compared with the traditional centrifugation method, 87.5 +/- 0.9% versus 76.1 +/- 1.3% (P less than 0.001). When comparing media with and without Hya in the self-migration method for preparation of normal sperm samples, the media containing Hya resulted in the recovery of a significantly higher percentage of motile spermatozoa, 89.0 +/- 0.8% versus 73.8 +/- 2.0% (P less than 0.001). In a group of 80 consecutive couples entering our IVF programme, sperm samples from 44 of the men were allocated at random for the self migration method in medium containing Hya and sperm samples from 36 men for preparation by centrifugation and swim-up. Significantly more pregnancies were achieved in the group prepared in medium containing Hya. It is concluded that self-migration of sperm in a medium containing Hya is simple and rapid, and results in a high recovery of motile spermatozoa which can be used for in-vitro insemination of human oocytes with favourable results.