Nervous System Anomalies in infants less than one year in the East coast of Spain

Abstract Background Congenital anomalies of nervous system (CANS) are an important health problem and represent a high perinatal and infant mortality due to their seriousness. Objectives to determine and describe the trend and distribution of CANS in the Valencian Region (VR) in children under one year of age, born in 2007-2022. Methods Live births (LB), stillbirths and termination of pregnancy for fetal anomaly with CANS were selected from the CA population-based registry of VR between 2007-2022. The study variables were described. Prevalence per 10,000 births and their 95% confidence intervals were calculated. In LB, the survival rate per week was estimated using the Kaplan-Meyer method. Results 1862 cases were identified, the overall prevalence was 26.1/10,000 births. The most common type of end-pregnancy was LB (54.6%), 60.3% of cases were detected prenatally and “Congenital Hydrocephalus” was the most frequent (20.7%). In LB, the survival rate was 94.9% and statistically significant differences were identified according to CANS: Anencephaly has the lowest (9%), and in others ranged from 90.9% for Encephalocele to 98.2% for Spina Bifida. Regarding the pregnant women in CANS cases, mean age was 31.9 years and majority birth country was Spain (69.1%). The group with less than 20 years has the highest prevalence (38.4/10,000 births). The province of Castellon (which has the smallest birth population) has the highest prevalence (34.1/10,000 births) and it had the highest percentage of pregnant women of Moroccan (10.6%) and Romanian (10.2%) origin. Conclusions The prevalence of cases with CANS was similar than European network registries of CA. Identifying higher prevalence of cases among the youngest pregnant women or residents in Castellon province, it could be due to the higher presence of pregnant women from countries where early pregnancy is more common within the sociocultural context. Key messages • In the East coast of Spain, youngest pregnant women has the highest prevalence of cases with nervous system anomalies. • Obtaining results from population-based registries allows to know the real situation of cases with congenital anomalies of the nervous system and also facilitates the implementation of health policies.