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).

Methods: Secondary analysis of prospectively collected registry data. Methods: Seven multiple-source, population-based congenital anomaly registers, members of the British Isles Network of Congenital Anomaly Registers (BINOCAR) in 2005 and 2006. Methods: 2,883 births with congenital anomalies from a total of 601,545 live and stillbirths. Methods: 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% CI 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% CI 43.5-65.2) for serious cardiac anomalies to 99.6% (95% CI 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.