Sonographic findings in a fetus with megacystis-microcolon-intestinal hypoperistalsis syndrome.

We describe the perinatal findings in a female fetus with megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS). Prenatal sonography performed during 18-21 weeks' gestation showed a normal amount of amniotic fluid, but the fetus was seen to have a persistently distended stomach, a hugely distended bladder, and bilateral dilated renal calyces. Genetic analysis of amniotic fluid revealed a 46,XX karyotype. The pregnancy was terminated at 22 weeks' gestation. At necropsy, the fetus was found to have prune-belly syndrome, gastric dilatation, pronounced megacystis, bilateral hydronephrosis and megaureters, short bowel, microileum, microcolon, and malrotation of the intestines. This fetus showed the typical clinical and sonographic features of MMIHS, as well as the rare antenatal finding of persistent gastric distention.