Liver volume in trisomy 21 and euploid fetuses at 11 to 13 weeks

OBJECTIVES: To compare liver volume between trisomy 21 and euploid fetuses at 11 to 13 weeks' gestation. METHODS: Fetal liver volume was measured by 3D ultrasound in fetuses at low risk of aneuploidies (n = 200) and another group at high risk, including 148 euploid and 37 with trisomy 21. The association of liver volume with fetal nuchal translucency (NT) thickness, tricuspid regurgitation and reversed a-wave in the ductus venosus was investigated. RESULTS: In the low-risk group, fetal liver volume increased exponentially with fetal crown-rump length (CRL) from a median of 0.5 cm(3) at CRL of 45 mm to about 2.5 cm(3) at CRL of 84 mm. In 27 (73.0%) of the trisomy 21 fetuses liver volume was above the 95th percentile of the low-risk group, whereas in the euploid fetuses liver volume was not significantly altered (P = 0.521). There were no significant contributions to liver volume from fetal NT (P = 0.508), tricuspid regurgitation (P = 0.958) or reversed a-wave in the ductus venosus (P = 0.872). CONCLUSION: In trisomy 21 fetuses at 11 to 13 weeks liver volume is increased.