title: Relationship between progesterone suppression and pregnancy in rats.
abstract: Four luteolytic agents were administered to groups of pregnant rats to examine the quantitative relationship between serum progesterone levels and the maintenance of pregnancy. Each agent inhibited progesterone in a dose-dependent manner, however only three, azastene, thiosemicarbazone and dihydrotestosterone, adversely affected pregnancy. A statistical analysis of the data suggests that, regardless of the mechanism of action of a particular luteolytic agent, a treatment-induced depression of serum progesterone to concentrations less than 45% of that of the controls on day 11 of pregnancy is incompatible with pregnancy maintenance.
mesh_terms: D000818:Animals; D005260:Female; D008186:Luteolytic Agents / Q000494:pharmacology*; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000097:blood / Q000187:drug effects*; D011374:Progesterone / Q000097:blood*; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D008186:Luteolytic Agents; D011374:Progesterone