Comparison of prenatal central nervous system abnormalities with postmortem findings in fetuses following termination of pregnancy and clinical utility of postmortem examination

Abstract

Objectives In this study, we aimed to compare prenatal ultrasound (USG) and postmortem examination findings of central nervous system (CNS) abnormalities in fetuses following termination of pregnancy (TOP). Methods A total of 190 fetuses with USG-confirmed fetal CNS abnormalities of terminated pregnancies between January 2001 and January 2017 were retrospectively analyzed and USG and postmortem examination findings were compared. Results The most frequent CNS abnormalities were acrania/anencephaly (n=45, 24%), spina bifida (n=43, 23%), and ventriculomegaly (n=35, 18%). In 144 of the 190 (76%) cases, there was total agreement between USG and postmortem examination diagnosis. Postmortem examination provided minor findings which did not change the major clinical diagnosis in two (1%) cases with spina bifida and ventriculomegaly. In six (3%) cases, the diagnosis changed after postmortem examination. In 25 of the 190 (13%) cases with multiple abnormalities as evidenced by USG, CNS abnormality was unable to be confirmed at postmortem examination. Conclusions Our study results show an overall high agreement (76%) between USG and postmortem examination findings for CNS malformations. Due to autolysis and fluid structure, USG-confirmed CNS diagnosis cannot be always confirmed by postmortem examination. This potential discrepancy should be explained to patients before considering TOP. Postmortem examination is the gold standard to confirm prenatal diagnosis.