Comparative study on the use of human follicular fluid or egg yolk medium to enhance the performance of human sperm in the zona-free hamster oocyte penetration assay

A prospective study was conducted on 61 unselected semen samples from infertile patients to compare the efficacy of human follicular fluid (hFF) or TEST-egg yolk medium treatment in enhancing sperm performance in the zona-free hamster oocyte penetration (HOP) test. Both hFF and TEST-egg yolk enhanced penetration scores significantly in the HOP test in comparison with the control swim-up sperm preparation. The TEST-egg yolk medium treatment, however, exhibited the highest penetration scores, and there were higher percentages of preparations passing the 10 or 20% penetration rate cut-off point with sperm exposed to the TEST-egg yolk medium than those exposed to hFF. These results indicate that modification of the original HOP-test protocol by incorporation of TEST-egg yolk medium gives a greatly increased penetration rate when compared to the addition of hFF in such a system.