- Late follicular phase postcoital tests in 355 infertile couples (selected to exclude severe defects in ovulation, seminal or tubal function) were scored for mucus characteristics and sperm motility. Cervical mucus characteristics were associated with postcoital sperm motility (P less than 0.001) but not with pregnancy. Postcoital sperm motility in cervical mucus was strongly associated with total motile sperm count per ejaculate (F = 5.38, P less than 0.001). Postcoital sperm motility was a weak predictor of pregnancy when more than five motile sperm were observed per high power microscopic field. When the log rank tests for postcoital sperm motility were repeated in groups with low (less than 10 million) and high (10 million or more) total motile sperm count per ejaculate, the association between postcoital sperm motility and pregnancy was not statistically significant. Regression analysis controlling for other potential predictors revealed no independent association between postcoital sperm motility and the later occurrence of pregnancy in this group of infertile couples.