The authors reviewed their experience with meconium peritonitis (MP) d
iagnosed in utero to define criteria for prenatal and postnatal manage
ment. Prenatal diagnosis was made by identifying abdominal calcificati
on on serial ultrasound examinations in nine fetuses, between 18 and 3
7 weeks' gestation. Cases without associated bowel abnormalities were
considered ''simple MP'' and those with bowel abnormalities were consi
dered ''complex MP.'' Five cases of simple MP were identified at 18, 2
3, 30, 34, and 37 weeks' gestation, These five fetuses were delivered
at term and had normal abdominal examinations. Abdominal radiographs w
ere obtained in three showing normal bowel gas patterns, and abdominal
calcifications in only two. All five patients were fed uneventually.
Four cases of complex MP were identified at 26, 26, 31, and 31 weeks'
gestation. All four fetuses had dilated loops of bowel. Two of the fou
r had meconium cysts, one of which was associated with ascites and the
other with polyhydramnios. Shortly after birth both infants with meco
nium cysts required ileal resection and ileostomy for ileal atresia an
d ileal perforation, respectively. The remaining two infants had no ev
idence of dilated bowel, meconium cyst, or ascites on postnatal radiog
raph and were fed uneventfully. These data suggest that only 22% of fe
tuses with a prenatal diagnosis of MP develop complications that requi
re postnatal operation. Gestational age at diagnosis does not correlat
e with postnatal outcome. Fetuses with complex MP are at increased ris
k for postnatal bowel obstruction and perforation. Copyright (C) 1995
by W.B. Saunders Company.