Cytophotometric DNA-measurements in abortion.

Triploid abortuses ascertained by cytogenetic analysis histologically show molar degeneration of the placental villi. Changes of this type which are occasionally encountered in routine material may suggest chromosome abnormality although chromosome analysis is precluded due to fixation. However, suspected triploidy can be proven in Feulgen-stained sections by DNA-measurements. In nine cases of molar degeneration selected according to histological criteria, evaluation of nuclear DNA-content revealed only two triploid placentae. It seems acceptable to assume that such molar changes in diploid abortuses may be due to prolonged retention of the placenta. Thus, histological criteria may suggest but cannot establish the diagnosis of triploidy. In case of susepcted triploidy of the feto-placental tissue, DNA-measurements can confirm or exclude the diagnosis even if a cytogenetical analysis is not applicable.