A Descriptive Study of Fetal Central Nervous System Anomalies Diagnosed Antenatally in a Tertiary Care Hospital in India

Abstract Central nervous system (CNS) malformations constitute a cohort of common fetal abnormalities. Due to the complexity and varied nature of CNS abnormalities, diagnosis is relatively difficult. In addition, the fetal brain continues to develop throughout pregnancy, showing major, obvious, and striking changes in the third trimester. Some abnormalities may be detected as early as the first trimester, whereas others may be detected only in the second or third trimesters. Through this study, an analysis of the various fetal CNS anomalies reported to a perinatal outpatient department of a tertiary care teaching hospital in Mumbai was conducted with reference to the spectrum of antenatally diagnosed CNS anomalies, time of usual presentation of each anomaly, perinatal outcomes, parental attitude to the disorder, as well as the usual methods of management of such anomalies. The findings of the study may improve subject knowledge and serve as a precursor for further studies on the subject. A retrospective descriptive study performed on all patients diagnosed with fetal CNS abnormalities on antenatal ultrasound and who presented to Nowrosjee Wadia Maternity Hospital, a tertiary care hospital in Mumbai, India, from January 1, 2020 to December 31, 2021. The case records of such patients were identified and their demographic data were recorded. A total of 174 patients were identified with fetal CNS disorders in the 2-year period. Almost one-third had spinal open neural tube defects and a fifth had isolated ventriculomegaly. A third of the patients had a significant family history of CNS disorders. Certain disorders have been diagnosed at or before 24 weeks of gestation; some disorders have been diagnosed in all trimesters, while yet others manifest only after 24 weeks of gestation. A fifth of fetuses had multisystem involvement, while the rest had apparently isolated CNS involvement. Of the 143 patients who delivered or aborted in our institution, the neonatal period was relatively uneventful in 18 (12%) cases only; 46 (32%) neonates were alive. In total, 89 parents (62%) terminated pregnancy, 8 (5%) had perinatal demise, and 28 (19%) neonates had some morbidity and were transferred to specialty neonatal care for medical or surgical management. The 5-year intact survival was only 8.8%. Fetal CNS disorders are a varied group of abnormalities that can present at varying gestational ages. A thorough knowledge of embryology, anatomy, and imaging is essential to diagnose and determine the prognosis of fetal CNS disorders.