Elective Termination of Pregnancies Due to Fetal Congenital Anomalies: Utility of Various Investigating Modalities for Etiological Diagnosis of Congenital Anomalies

Introduction: Etiological diagnosis of congenital anomalies greatly influences further reproductive genetic counseling. We herein report our experience of using various modalities for identification of the same. Materials and Methods: Pregnancies undergoing elective termination due to fetal congenital anomaly(ies) detected on antenatal ultrasonography were enrolled. Fetal autopsy, radiological studies and histopathology were done in all cases. Chromosomal Microarray (CMA) and Exome sequencing (ES) was done in selected cases. Results: One hundred seventy-four fetuses were enrolled. In 19.4% of cases a change in diagnosis/recurrence risk was observed based on a finding in autopsy. Utility of radiology and histopathology was observed in 5.7% and 13.4% of a selected subgroup of the cohort respectively. 39 cases (22%) were taken up for genetic testing. In this selected cohort overall positivity rate of genetic testing was 43.5% (28% and 71% for CMA and ES respectively). Conclusion: A phenotype-driven and systematic approach has the highest yield in detecting causes of fetal congenital anomalies.