Quantitative post-coital test: sperm counts in cervical mucus after enzymatic liquefaction

The post-coital test involves direct microscopic examination of sperm number and motility in cervical mucus. The results depend on the quality of the mucus and the distribution of spermatozoa within the sample. To progress from such qualitative data to quantitative measurements of the spermatozoa present in post-coital mucus, we have developed methods to measure sperm concentrations in enzymatically liquefied post-coital cervical mucus. The mucus score and sperm motility were measured prior to mucus liquefaction, and, together with sperm concentration, they allowed the calculation of the total number of motile spermatozoa present. A combination of bromelin and glycosidases proved to be more efficient in achieving reliable mucus liquefaction than treatment with bromelin alone, and was used to liquefy a series of 36 post-coital test samples. Total sperm numbers ranged between 19 x 10(3) and 16.8 x 10(6). Of the samples, 75% contained < 3 x 10(6) spermatozoa, and 39% contained < 1 x 10(6) spermatozoa. Sperm motility was very high in these samples, except for a distinct subset of samples (19%) in which the total sperm motility was markedly decreased ( < 20%). The measurement of sperm concentration in liquefied cervical mucus will help to determine normal values for the post-coital test, and to estimate the number of motile spermatozoa reaching the upper female genital tract.