A practical, objective approach to the evaluation of sperm and cervical mucus in humans

Human sperm fertility potential, expressed as a quality index (QI), was evaluated objectively from considerations of sperm velocity, percentage of motile forms, sperm density, and ejaculate volume. Turbidimetry was applied in the quantitation of sperm velocity. High QIs (700) were characteristic of semen samples that were capable of penetrating cervical mucus in capillary tube penetration tests, while low QIs (80) were associated with specimens that did not penetrate mucus. The rate of decline in QI as a function of time postejaculation was determined for samples stored at 37 degrees C and at ambient temperature, providing correction factors for the comparative evaluation of semen samples analyzed at different times. The penetrability of cervical mucus was determined by capillary tube penetration testing. Subsequent chemical analysis of sperm-penetrable and impenetrable samples indicated that the concentrations of mucus nondialyzable solids (NDS), mucins, and soluble proteins were significantly higher in impenetrable specimens. These characteristics were also observed in impenetrable mucus obtained from patients with cervical factor infertility. These studies indicate that it is now feasible to employ mucus [NDS] in the diagnosis of cervical factor infertility and turbidimetry in the evaluation of human sperm quality.