Human oviductal fluid prolongs sperm survival

Objective: To compare the effect of human oviductal fluid on sperm motility and hyperactivation during 9 hours' incubation in vitro with follicular fluid (FF) and medium controls.

Design: Fertile donor spermatozoa were allowed to penetrate human cervical mucus in vitro and then recovered and incubated in either 30% human oviductal fluid, 20% FF, or medium for up to 9 hours. Sperm motion characteristics were measured using a sperm motility analyzer.

Setting: The donor insemination program at the University Clinic within the Jessop Hospital for Women, Sheffield, United Kingdom.

Patients: All donors used in this study were involved in the donor insemination program.

Main outcome measures: Sperm motility, hyperactivation, curvilinear velocity, progressive, lateral head displacement, and linearity were measured using a sperm motility analyzer.

Results: After 9 hours' incubation, spermatozoa in human oviductal fluid had a significantly higher percentage motility than sperm incubated in FF or the control medium. A more linear sperm motion was consistently observed in the spermatozoa incubated in human oviductal fluid: significantly different from FF and media at 3 hours and 6 hours. The effect of human oviductal fluid on maintaining sperm motility was not affected by the addition of P.

Conclusion: Human oviductal fluid can maintain sperm motility in a mechanism that is not mediated by the low concentration of P. We suggest that human oviductal fluid is a favorable environment for sperm survival.