[Pregnanediol excretion in the sexual cycle dynamics of white rats guinea pigs and hamsters].

A study was made of pregnandiol excretion with the 24-hour urine of albino rats, guinea pigs and hamsters at various phases of the esteral cycle. Excretion of metabolities of the principal hestagens (progesterone and 20-alpha progesterone) in the form of alpha- and beta-isomers of pregnandiol proved to be definitely cyclic in character. The periodicity of pregnandiol excretion in the three types of experimental rodents reflected the course of the synthesis and secretion of hestagens, with a delay for a cycle phase. The maximal excretion of both pregnandiol isomeres with the 24-hour urine was abserved in albino rats during the estrus and metestrus, and in guinea pigs and Cricetus auratus W.--during the estrus and diestrus.