Prenatal diagnosis of oesophageal atresia.

Oesophageal atresia (OA), often associated with tracheo-oesophageal fistula (TOF), is the most common congenital anomaly of the upper gastrointestinal tract. Despite advances in imaging, prenatal diagnosis remains challenging, with detection relying mainly on indirect sonographic signs such as polyhydramnios or a small/absent stomach bubble. Direct markers, including the “upper pouch” and “distended hypopharynx” signs, offer greater specificity (95% and 67%, respectively) but are inconsistently identified and often emerge late in gestation. Fetal MRI has enhanced diagnostic accuracy by visualising the proximal pouch and assessing swallowing dynamics, though many cases continue to be diagnosed postnatally. Estimating the biochemical EA Index, based on amniotic fluid alpha-fetoprotein (AFP) and Gamma-glutamyl transpeptidase (GGT), has shown initial promise with sensitivity and spaecificity over 90%, but is invasive and needs validation in larger studies. Accurate prenatal recognition is essential to guide multidisciplinary counselling, optimise perinatal management, and ensure delivery in centres with paediatric surgical expertise. While prognosis is excellent in isolated cases, survival and long-term outcomes are significantly compromised when additional malformations are present. Integrating ultrasound, MRI, and, in selected cases, biochemical analysis provides the best framework for improving detection and management apporaches.