Human sperm penetration in bovine cervical mucus clinical studies. II. Use of split ejaculates

Sperm penetration through bovine cervical mucus was determined and correlated with the sperm characteristics in three fractions of the split ejaculate and in the whole ejaculate from 40 men of infertile couples in which a female cause of infertility had been ruled out. Sperm concentration and motility were found to be significantly higher in the first fraction (n = 40) as compared with the rest of the fractions and the whole ejaculate, whereas normal sperm morphology was not significantly different among the various fractions and the whole ejaculate. The bovine mucus penetration (BCMP) test was found to be normal in a significantly high percentage (58%) of samples of the first fraction as compared with the other two fractions (32% and 17%, respectively) and the whole ejaculate (35%) (n = 17). Moreover, in the first fraction of the split ejaculate, the results of the BCMP test were correlated significantly with sperm concentration (P less than 0.01), motility (P less than 0.0001), and morphology (P less than 0.02). The data demonstrate the superiority of the first fraction of the split ejaculate in terms of cervical mucus penetrability and sperm characteristics.