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.