Evaluation of prenatal diagnosis of congenital gastro-intestinal atresias.

Prenatal diagnosis performed by fetal ultrasound scan is now a routine part of antenatal care in many countries. That an increasing number of fetal anomalies may be detected on prenatal ultrasound is beyond doubt. However what is theoretically possible is not, always done in practice specially when gastrointestinal atresias (GIA) are concerned and when whole antenatal populations are screened rather than high risk groups. Thanks to our registry of congenital anomalies a retrospective study was undertaken to evaluate the prenatal detection of GIA by ultrasound scan in 118,265 consecutive pregnancies of known outcome. Only 31 out of 129 malformed fetuses with GIA were detected (24.0%). The sensitivity of detection varied from 51.4% for atresia of the small intestine to 24.2% for esophageal atresia and 8.2% for ano-rectal atresia. No isolated case with esophageal atresia and ano-rectal atresia were diagnosed. Our results stress the need to perform scans at > or = 18 weeks gestation and to train sonographers in order to improve prenatal detection of GIA.