Polyacrylamide as a substitute for cervical mucus in sperm migration tests.

A synthetic migration medium for capillary sperm migration studies was developed. Parallel sperm migration in 1.8% polyacrylamide cross-linked with 0.042% N,N'-methylene bis acrylamide was similar to sperm migration in bovine cervical mucus. Bull spermatozoa varying widely in migration distances in bovine cervical mucus maintained similar relative migration distances in this synthetic medium. The advantages of the synthetic medium are its availability in large quantities, its uniformity, and its stability. There was no change in parallel sperm migration distances in the synthetic medium stored at 4 degrees C for up to 4 months. Use of this synthetic medium for human or bovine sperm migration studies would appear to overcome problems associated with the variability of cervical mucus.