The most prominent symptoms of duodenal atresia include: - Bilious vomiting: Vomiting that contains bile, typically green or yellow in color, usually occurring within the first 24-48 hours after birth. - Abdominal distension: Swelling of the baby's abdomen due to the accumulation of stomach contents. - Failure to pass meconium: The newborn may not pass their first stool, which is typically dark and sticky. - Feeding difficulties: Inability to keep milk down leading to poor feeding and dehydration.