Fetal gastric size in normal and abnormal pregnancies.
OBJECTIVE
The aim of this observational study was to construct an ultrasound index of fetal gastric size for the prenatal detection of congenital digestive tract obstruction.


METHODS
A total of 386 fetal measurements were performed in routine ultrasonographic examinations of women with normal singleton pregnancies between 18 and 39 weeks of gestation. Gastric measurements were also performed in 13 fetuses with digestive tract obstruction.


METHODS
The ultrasound plane which included the pylorus and which provided the largest stomach area was used for definition and measurement of gastric area and maximal longitudinal dimension. The transverse section at the center of the gastric corpus was used for transverse and anteroposterior dimensions. Gastric volumes were calculated as a prolate ellipsoid. The gastric area ratio was defined as the gastric area divided by the transverse abdominal area. Biparietal diameter (BPD) and abdominal transverse area were also measured.


RESULTS
The fetal gastric area was significantly correlated with fetal gastric volume (r = 0.91) and gestational age (r = 0.74). However, the correlation coefficient for gastric area with gestational age was smaller than those of the BPD (r = 0.97) with gestational age and abdominal transverse area with gestational age (r = 0.97). Gastric area ratio decreased slightly towards term. The gastric area ratio was below the 95% confidence intervals for the predicted values in all five fetuses with esophageal atresia, and exceeded the 95% confidence intervals in seven of the eight fetuses with duodenal atresia or intestinal tract obstruction.


CONCLUSIONS
Fetal gastric area correlates with ultrasound-determined gastric volume measurements and appears to be useful in the assessment of digestive tract anomalies.
Sase
M
M
Department of Reproductive, Pediatric and Infection Science, Yamaguchi University School of Medicine, Ube, Japan. sase@po.cc.yamaguchi-u.ac.jp
Asada
H
H
Okuda
M
M
Kato
H
H
D016022:Case-Control Studies; D016001:Confidence Intervals; D005314:Embryonic and Fetal Development / Q000502:physiology; D005260:Female; D005767:Gastrointestinal Diseases / Q000000981:diagnostic imaging* / Q000196:embryology; D005865:Gestational Age; D006801:Humans; D011247:Pregnancy; D011336:Probability; D011707:Pyloric Stenosis / Q000000981:diagnostic imaging* / Q000196:embryology; D012016:Reference Values; D012680:Sensitivity and Specificity; D013270:Stomach / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000196:embryology*; D016216:Ultrasonography, Prenatal / Q000379:methods*