[Effect of pregnancy on the biotransformation of aminophenazone]

During delivery there was found a prolongation of the halflife-time of Aminophenazon in comparison with a group of non-pregnant women. Thinlay-chromatography investigations of the metabolitspektrum show, that the cause of this fact is a changed biotransformation in pregnancy. The placental share in metabolism of Aminophenazon is very small. The influence of gestagens concerning the biotransformation is discussed.