RESUMO
PIP: A study was undertaken to compare the prolonged estrogenicity and antifertility properties of quinestrol and 4 analogues in rats. The following assays were used: 1) vaginal cornification; 2) uterine growth;and 3) timed pregnant rats. The last assay involved the administration of test compounds to pregnant rats at various times after mating and subsequent observation, on Day 19 after mating, of the number of continuing pregnancies, the weights of the uteri containing fetuses and placentas, and the number of fetuses or implantation sites. All of the quinestrol analogues had prolonged estrogenic activity as shown by the assays used, but quinestrol had the most protracted duration of activity. No correlation was seen between the chemical structure of the compounds and activity in the 3 assays.^ieng
