Prognostic significance of nonvisualization of the fetal stomach by sonography

To establish the prognostic significance of nonvisualization of the fetal stomach, we prospectively studied the course and outcome of 31 pregnancies in which a normal fluid-filled fetal stomach could not be seen during sonographic examination after 14 weeks' gestation.

Between April 1989 and May 1991, 7200 sonographic examinations of fetuses after 14 weeks' gestation were done at our hospital. In 31 pregnancies (0.4% of all scans), a normal fluid-filled fetal stomach could not be seen on one or more sonograms after 14 weeks' gestation (range, 14-40 weeks; mean, 22 weeks). The following data were recorded for each examination: gestational age, visualization of the stomach, other fetal abnormalities, and volume of amniotic fluid. In each pregnancy, the average number of sonograms obtained was three (range, one-five). The fetal stomach was regarded as abnormal if the stomach bubble was absent or remained very small and unchanged for at least 45 min during sonography.

The outcome was normal in 16 cases. The 15 abnormal outcomes included spontaneous fetal or neonatal death in five, pregnancy terminations in three, and persistent postnatal disability in seven. In 15 pregnancies (48%) lack of visualization of the fetal stomach was the only significant abnormal sonographic finding, but an abnormal outcome occurred in three. In 12 pregnancies, nonvisualization of the fetal stomach was a transient finding, yet three of those pregnancies resulted in persistent postnatal disability, and one was terminated because of severe maternal preeclampsia. A normal fluid-filled stomach was seen on the next sonogram in 15 cases, but five had an abnormal outcome. Only one of the four pregnancies in which a normal stomach was not seen on any subsequent sonogram had an abnormal outcome. Six of seven pregnancies with oligohydramnios had an abnormal outcome, and all three cases with polyhydramnios had an abnormal outcome. The prevalence of abnormal outcome was 88% when additional sonographic abnormalities were observed, but 20% when no other sonographic abnormality was seen. The overall prevalence of abnormal outcome when the fetal stomach was not visualized was 48%.

Not all fetuses with a nonvisualized stomach after 19 weeks' gestation have a poor outcome. Not all fetuses with a transiently nonvisualized stomach have a normal outcome.