Prevalence of Congenital Anomalies in an Indian Maternal Cohort: Healthcare, Prevention, and Surveillance Implications.

Abstract

BACKGROUND: India lacks a national birth defects surveillance. Data on the prevalence of congenital anomalies are available mostly from hospital-based, cross-sectional studies. This is the first cohort study from India, where 2107 women were followed till pregnancy outcome, in order to measure the prevalence and types of congenital anomalies, their contribution to neonatal mortality, implications for surveillance, and the health service needs for prevention and management. METHODS: The study followed a cohort of 2107 pregnant women till outcome which was miscarriage, termination of pregnancy, live or stillbirth, neonatal and post-neonatal mortality. Case ascertainment of congenital anomalies was done through visual examination, followed by various investigations. Rates of congenital anomaly affected births were reported per 10 000 births. Health service needs were described through retrospective analysis of events surrounding the diagnosis of a congenital anomaly. RESULTS: Among 1822 births, the total prevalence of major congenital anomalies was 230.51 (170.99-310.11) per 10 000 births. Congenital heart defects were the most commonly reported anomalies in the cohort with a prevalence of 65.86 (37.72-114.77) per 10 000 births. Although neural tube defects were two and a half times less as compared to congenital heart defects, they were nevertheless significant at a prevalence of 27.44 (11.73-64.08) per 10 000 births. In this cohort, congenital anomalies were the second largest cause of neonatal deaths. The congenital anomaly prenatal diagnosis prevalence was 10.98 per 1000 births and the congenital anomaly termination of pregnancy rate was 4.39 per 1000 births. CONCLUSIONS: This first cohort study from India establishes that the congenital anomaly rates were high, affecting one in forty four births in the cohort. The prevalence of congenital anomalies was identical to the stillbirth prevalence in the cohort, highlighting their public health importance. The results of this study identify the need for a well defined national programme with components of prevention, care and surveillance.