Long-term follow-up of couples after hamster egg penetration testing

Objective: To determine the clinical usefulness of the zona-free hamster egg penetration test as a long-term prognostic indicator for future pregnancy. Setting: Division of Reproductive Endocrinology and Infertility at the Washington University Medical Center. Participants: All couples (n = 148) who had a hamster egg penetration assay performed between March 1, 1985 and December 31, 1986 were identified and followed with direct or telephone contact up to 68 months after the initial assay. Main Outcome Measure: The monthly fecundity rates using life table analysis and the 5-year incidence of pregnancy were categorized by the percentage of hamster eggs penetrated and by history of previous urologic surgery. Results: There were no significant differences in the rate nor incidence of pregnancy in couples with hamster egg penetration scores of 0%, >0% and ≤10%, >10%, and ≤20%, or >20%. Although men with previous urologic surgery tended to have lower scores, there was no significant difference in the 5-year incidence of pregnancy. Conclusion: The hamster egg penetration score is not predictive of incidence of pregnancy nor time to conception.