Nonvisualized, dilated or even a small fetal stomach can be associated with a variety of anomalies and poor fetal outcome. Therefore, we attempted to evaluate the stomach circumference (SC)/abdominal circumference (AC) ratio to assess normal limits of fetal stomach size. A total of 363 fetuses ranging from 15 to 39 weeks' gestation were prospectively evaluated with ultrasonography. The SC was measured from a plane that is perpendicular to the fetal longitudinal axis at the level where the largest axial circumference of the stomach was obtained using a digitizer. The AC was also measured at the same section and the ratio was calculated by dividing the SC by the AC and multiplying by 100. The SC increased linearly from 15 to 24 weeks and showed fluctuations in size thereafter to 39 weeks. A strong correlation was noted between gestational age and both SC (r: 0.842, P <0.0001) and AC (r: 0.975, P <0.0001). The SC/AC ratio was normally distributed with a mean of 20.4 +/- 3.9% and ranged between 14.8% and 27.03% throughout pregnancy (r: 0.021, P > 0.05). Although the fetal stomach is a dynamically changing organ, the SC/AC ratio can be considered as a potentially useful parameter in assessing fetal stomach size.
Abdomen/embryology* ; Cross-Sectional Studies ; Fetal Development/physiology ; Fetus/anatomy & histology* ; Gestational Age ; Human ; Prospective Studies ; Stomach/embryology* ; Ultrasonography, Prenatal

OBJECTIVETo assess the state of the art of fetal magnetic resonance imaging (MRI) in China.

DATA SOURCESBoth Chinese and English language literatures were searched in the databases of PUBMED (1998-2005) and CNKI (1998-2005), 41 published articles about fetal MRI were selected.

RESULTSFetal MRI can serve as an adjunct tool for ultrasonography because of its excellent soft tissue contrast, high spatial resolution, multiplanar capabilities, large field of view and simultaneous visualization of fetal and maternal structures. Since the development of ultrafast MRI sequences provides faster scan time and avoids motion artifacts, it is widely applied in detecting normal or abnormal fetal development, including the central nervous system, thoracic region, abdomen and others. In China, experience in fetal MRI has been scanty, but the technique will be extensively used in the near future because of its multi-faceted advantages.

CONCLUSIONSCompared with ultrasonography, MRI as a complementary imaging for fetal screening is prospective in China or other parts of the world because of its multiple superiorities.

Abdomen ; abnormalities ; embryology ; Cell Movement ; Central Nervous System ; abnormalities ; embryology ; Congenital Abnormalities ; diagnosis ; Female ; Fetus ; anatomy & histology ; Humans ; Magnetic Resonance Imaging ; methods ; Myelin Sheath ; physiology ; Pregnancy ; Thorax ; abnormalities ; embryology