the time course of the concentration of the 14c- and 3h-labelled substances and of unchanged norethisterone was determined in maternal plasma and selected tissues of the feto-placental unit after intragastric administration of a combination of 14c-norethisterone acetate ( net-ac ) and 3h-ethinylestradiol ( ee2 ) , respective commercial formulation : ostro - primolut , to pregnant rats .
C0028356
norethisterone
C0068980
norethisterone acetate