Der Acardius amorphus

Abstract
We report on an acardius in a 47-year old tenthgravida. The postnatally detected acardius did not cause any obstetrical problems. The following theory seems to be the most suitable explanation for the development of an acardius: in a twin (multiple) pregnancy with blood vessel anastomoses between both twins, a twin with a haemodynamic advantage supplies the other one with oxygen-deprived blood; the latter thus becames an acardius.