Variation in, and inter-relationship between, prostaglandin levels and other semen parameters in normal men

In each of 135 ejaculates from 46 healthy men, semen volume, various sperm parameters and the level of prostaglandins (PGs) were determined. Data were analysed to determine the within- and between-subject variability, the effect of abstinence period and the correlation between different parameters. Data which did not reveal a Gaussian distribution were transformed logarithmically. For all variables the between-subject variance exceeded the variation within subjects (P less than 0.001). Variation in time of abstinence between 1 and 3 days influenced semen volume and sperm content as well as the content of 19-hydroxylated PGs, but did not affect sperm motility or the concentration of PGE or PGF. A significant negative correlation was found between the seminal content of PGE and PGF and the total sperm count as well as the sperm concentration. Sperm motility was related to the balance between the content of 19-hydroxy PGE and 19-hydroxy PGF but not to their separate concentrations. The ratio between 19-hydroxy PGE and 19-hydroxy PGF did not change when the time of abstinence differed. Synthesis of the two 19-hydroxylated PGs seemed to be regulated by the same mechanism, but their hydroxylation capacity still varied considerably between individuals.