EVALUATION OF POLYACRYLAMIDE-GEL AS SUBSTITUTE FOR HUMAN CERVICAL-MUCUS IN THE SPERM PENETRATION TEST

Objective: To compare polyacrylamide gel as synthetic medium with huma n cervical mucus (CM) for the in vitro sperm-penetration test during i nfertility investigation. Patients: One hundred sixty-nine randomly ch osen couples with a median duration of infertility of 4 (range, 1 to 1 6) years presenting at the infertility unit of the Women's University Hospital of Heidelberg, Germany. Main Outcome Measures: Evaluation of sperm migration in polyacrylamide gel used in four different concentra tions (1.5%, 1.6%, 1.7%, 1.8%) in the capillary tube test in parallel with CM of patients' female partners and CM of fertile donors, obtaine d under standardized conditions. Correlation of migration test results with outcome of semen analysis including microbial cultures and testi ng for local antisperm antibodies by means of the mixed antiglobulin r eaction, postcoital testing, and the subsequent pregnancy rate after c ontrol for female infertility factors in a prospective study. Results: Sperm ability to penetrate the synthetic medium (concerning all conce ntrations) correlated significantly with the penetration of human CM, although polyacrylamide proved to be a stronger barrier. Sperm velocit y and duration of progressive motility were markedly reduced in polyac rylamide. Polyacrylamide results correlated with the outcome of standa rd sperm analyses but not with sperm antibody testing. No clear differ entiation was obtained with regard to subsequent fertility (19% after 6 months), although adequate sperm migration in polyacrylamide 1.8% wa s significantly more frequent in the fertile group. Conclusions: In an alyzing the intrinsic motility, penetration testing with polyacrylamid e gel provides important information not obtained by routine sperm ana lysis. However, particularly with regard to immunological factors and fertility prognosis, human CM should be preferred whenever possible.