Background: Prenatal ultrasound (US) diagnosis of fetal intra-abdominal calcification (iAC) is frequently caused by an in utero perforation causing meconium peritonitis. Our ability to predict which fetuses will require postnatal surgery is limited. The aim of our study is to correlate iAC and associated US findings with postnatal outcome.

Methods: A single centre retrospective review of all cases of fetal iAC diagnosed between 2004 and 2010 was performed. Maternal demographics, fetal US findings, and outcomes (need for surgery and mortality) were collected. Descriptive and comparative statistical analyses were performed.

Results: Twenty-three cases of iAC were identified. There were no cases of fetal demise or postnatal deaths. Three liveborns (13%) required abdominal surgery at a median of 2 days (0-3) for intestinal atresia. US findings of iAC and dilated bowel with (p=0.008) or without (p=0.005) polyhydramnios predicted a need for postnatal surgery as did the combination of iAC, polyhydramnios, and ascites (p=0.008). Conversely, iAC alone or associated with oligohydramnios, polyhydramnios, ascites, or growth restriction did not predict need for postnatal surgery.

Conclusions: The majority of fetuses with iAC on prenatal US do not require surgery. Associated US findings (bowel dilation) can be used to select fetuses for delivery in neonatal surgical centres.