Objective: To evaluate the Penetrak (Serono Laboratories, Norwell, MA) and Tru-Trax (Humagen, Charlottesville, VA) bovine cervical mucus (CM) penetration assays and to correlate results to parameters of semen analysis and male factor diagnosis.
Design: Prospective, nonrandomized, controlled study.
Participants: Two hundred thirty-six males undergoing evaluation for male factor infertility and 37 fertile semen donors.
Main outcome measures: Human sperm penetration in bovine CM measured by the Penetrak and Tru-Trax assay systems correlated to sperm density, motility, forward progression, and clinical diagnosis.
Results: Two parameters of semen analysis, motility and density were correlated to the distance traversed by the vanguard sperm in both Penetrak and Tru-Trax assays. Penetrak results were significantly correlated to male factor infertility diagnosis.
Conclusions: Both assays were reliable and highly reproducible, and the Tru-Trax assay was correlated to its predecessor, Penetrak. Although Penetrak and Tru-Trax were correlated to motility and density, no correlation coefficient was > 0.6, suggesting that these assays measure a facet of sperm function that is independent of semen analysis.