Study on the prevalence and neonatal lethality in patients with selected congenital anomalies as per the data of the National Registry of Congenital Anomalies of Argentina.

INTRODUCTION: Congenital anomalies (CAs) account for 26% of infant mortality in Argentina. The lethality rate for CAs measures the risk of death among affected infants.

OBJECTIVES: To describe the prevalence at birth of a group of selected CAs, to estimate the neonatal lethality rate, and to examine its association with different variables.

POPULATION AND METHODS: The study was conducted using data provided by the National Registry of Congenital Anomalies. Prevalences of encephalocele, spina bifida, gastroschisis, omphalocele, diaphragmatic hernia, esophageal atresia, intestinal atresia, or anorectal malformation were estimated (2009-2013 period). Lethality was assessed at 7 and 28 days of life in affected infants with an isolated anomaly (2013). Association with the following variables was analyzed: sex, gestational age, birth weight, antenatal ultrasound screening, percentage of unmet basic needs in the district where the mother lives, geographic region, and level of care at the hospital where the delivery took place.

RESULTS: Gastroschisis was the most prevalent CA (8.53/10,000 births), while diaphragmatic hernia was the CA with the highest neonatal lethality rate (66.67%). Out of all selected CAs, there was a significant association between an higher gestational age and survival at 7 days -OR: 0.81 (0.70-0.95)- and survival at 28 days -OR: 0.79 (95% confidence interval |-CI-|: 0.68-0.91)-. A higher percentage of unmet basic needs was associated with a higher lethality for diaphragmatic hernia -OR: 1.59 (95% CI: 1.30-1.95)- and for intestinal atresia or anorectal malformation -OR: 16.00 (95% CI: 1.63-157.24)-.

CONCLUSIONS: The high prevalence of gastroschisis is consistent with the increase observed globally. Prematurity and a high percentage of unmet basic needs increased the risk of death among affected infants.