Congenital anomalies (CAs) affect about 3% to 4% of all births and are a major cause of perinatal and infant mortality, morbidity and disability.[1], [2], [3], [4], [5] Registries of CAs play a key role in the epidemiological surveillance of CAs. In France, there are seven registers of CAs that cover about 25% of all births. They routinely collect data on all births (live births, stillbirths and terminations of pregnancy for fetal anomaly [TOPFA]) with CAs, including genetic anomalies in a specific geographical area. Registries aim to monitor changes in the prevalence of CAs, identify potential clusters and teratogenic exposures. They can also serve as instruments for assessing the impact of healthcare, including prenatal diagnosis and TOPFA, and pregnancy outcomes.

France has an active, well-codified and fully reimbursed policy of prenatal screening for CAs. One ultrasound examination is recommended at each trimester of pregnancy for all pregnant women, and Down syndrome screening is also offered to all pregnant women during the first or the second trimester of pregnancy. In addition, French law allows TOPFA at any gestational age if the child is expected to have a “serious illness, recognized as incurable at the time of diagnosis.”[6]

Genetic techniques and prenatal diagnosis have improved considerably over the last decades. However, there are few published studies on the monitoring of CAs in France and the proportions of CAs detected prenatally and by TOPFA, in line with these changes. Therefore, this study aimed to provide epidemiologic data on the surveillance of CAs, including the proportions of prenatal diagnosis and TOPFA, from the Paris Registry of Congenital Malformations (remaPAR) from 1981 to 2020.