Comparison of the in vitro sperm penetration test using human cervical mucus and bovine estrus cervical mucus with the postcoital test.

The objective of this study was to determine how well bovine estrus cervical mucus could be substituted for human cervical mucus in the in vitro sperm penetration test (SPT) and how well the SPT compares with the postcoital test (PCT). The subjects were couples chosen at random from our infertility clinic population. The complete infertility evaluation of these couples included a PCT performed at the time of anticipated ovulation. Human cervical mucus quality was assessed using a scoring system which evaluated amount, spinnbarkeit, ferning, viscosity, and cellularity. SPT's were performed in flat capillary tubes filled with cervical mucus and exposed to semen samples for 90 minutes. Thirty-five couples had SPT's performed with wife's mucus and bovine mucus. Test results showed that PCT results correlated significantly with the SPT (P 0.02) but r was low (r = 0.37). The cervical mucus score correlated well with the SPT (P 0.001, r = 0.52) but less well with the PCT (P 0.03, r = .30). It is concluded that the SPT performed with either wife's mucus or bovine mucus is not an adequate substitute for the PCT but provides complementary information.