Omphalocele can be diagnosed while the baby is still in the womb. Ultrasound imaging during routine pregnancy checkups can detect omphalocele. Some blood test values may also be elevated above normal ranges. In children diagnosed with omphalocele, additional tests, such as cardiological checks, may be necessary, as other anomalies may be present.

Omphalocele can sometimes be confused with other abdominal wall defects, such as gastroschisis. Determining the type and severity of the abdominal wall defect is important for proper treatment planning. It is also important for babies diagnosed with omphalocele in utero to be delivered at appropriate hospitals with pediatric surgical capabilities.