Monitoring the prenatal detection of structural fetal congenital anomalies in England and Wales: register-based study

Objective To provide current population-based prevalence and prenatal diagnosis rates (PND) for specified major congenital anomalies in England and Wales to enable monitoring of the Fetal Anomaly Screening Programme (FASP). Design Secondary analysis of prospectively collected registry data. Setting Seven multiple-source, population-based congenital anomaly registers, members of the British Isles Network of Congenital Anomaly Registers (BINOCAR) in 2005 and 2006. Population 2,883 births with congenital anomalies from a total of 601,545 live and stillbirths. Main outcome measures PND and birth prevalence of selected congenital anomaly groups/subtypes (anencephaly, spina-bifida, serious cardiac, diaphragmatic hernia, gastroschisis, exomphalos, bilateral renal agenesis, lethal/severe skeletal dysplasia, cleft lip with or without cleft palate [CL + / - P]). Results Of the selected anomaly groups, the most frequently reported were serious cardiac (14.1 per 10,000 births [95% Cl 13.0-15.2]) and CL + / - P (9.7 per 10,000 births [8.9-10.5]); the least frequent were bilateral renal agenesis and lethal/severe skeletal dysplasia (<1.5 per 10,000 births). The PND varied for different anomalies from 53.1% (95% Cl 43.5-65.2) for serious cardiac anomalies to 99.6% (95% Cl 97.9-100.0) for anencephaly. Least variation in PND rates was for anencephaly (range 98.9-100%) and gastroschisis (93.5-100%); greatest variation was for serious cardiac (43.5-65.2%) and lethal/severe skeletal dysplasias (50.0-100%). Conclusions BINOCAR registers can, uniquely, provide contemporary data on PND and birth prevalence rates to enable monitoring of the ultrasound component of FASP at a national and regional level, allowing comparisons between populations to be made, planning of resources facilitated and assistance for parents making informed decisions on whether to enter the screening programme.