In utero appearance of a giant Meckel's diverticulum.

The authors present a case of a Meckel's diverticulum identified during a routine prenatal ultrasound examination as a complex mass, superior and posterior to the urinary bladder, that prompted meticulous postnatal evaluation. A 4.0-cm Meckel's diverticulum containing heterotopic gastric mucosa was excised before complications could arise. Meckel's diverticulum should be included in the differential of a complex intraabdominal mass of the fetus/neonate.