The document, published by INSA's Department of Epidemiology, reinforces the country's diagnostic excellence but highlights the continuous need to invest in pre-conceptional health awareness and accessibility to early pregnancy surveillance.
RENAC, operational since 1997, is a population-based nosological registry that reports the occurrence of Congenital Anomalies (AC) in Portugal. It records cases diagnosed in newborns, stillbirths, and fetuses undergoing medical termination of pregnancy after diagnosis of a severe malformation. Its objectives include providing information on AC epidemiology, maintaining a surveillance system to detect new teratogenic exposures, evaluating the impact of prenatal diagnosis, making data available for AC research, and integrating the European network of AC registries.
The 2022-2023 results highlight congenital heart defects as the most prevalent (58.2 cases/10,000 births), followed by musculoskeletal system anomalies (34.6 cases/10,000), chromosomal anomalies (27.3 cases/10,000), urinary tract anomalies (25.8 cases/10,000), and central nervous system anomalies (22.8 cases/10,000).
Prenatal diagnosis of AC occurred in 64% of reported cases, reflecting the effectiveness of secondary prevention. However, pre-conceptional folic acid supplementation, crucial for primary prevention of neural tube defects, is initiated before pregnancy by only 16.4% of women. The frequency of poorly monitored pregnancies showed an increasing trend, standing at 6.1%.
Perinatal mortality in cases with AC remained stable, ranging between 4.1% in 2022 and 5.1% in 2023. The national distribution of AC aligns with that observed by the European network EUROCAT, reflecting the high quality of diagnosis and the robustness of RENAC reporting.
Since 1997, RENAC, based at INSA's Department of Epidemiology, has been monitoring births with AC and tracking prevalence, geographical distribution, and risk factors, as well as overseeing prevention measures. The available data aims to empower professionals and policymakers to optimize AC prevention strategies.
