Normal Length of the Fetal Liver from 14 to 40 Weeks of Gestational Age

Objective: To create a normal reference table of fetal liver length in normal fetuses

Methods: A prospective, cross-sectional study was conducted on normal pregnancies with accurate gestational age (GA) from 14 to 40 weeks of gestation. All fetuses were measured for fetal liver length from the top of the right hemidiaphragm to tip of the right liver lobe on coronal image of the fetal abdomen, using high-resolution real-time ultrasound with a 2- to 4-MHz convex transducer.

Results: A total of 685 normal pregnant women between 14 and 40 weeks of gestation were recruited. Forty-five were excluded due to poor image quality and fetal abnormalities. The remaining 640 were available for analysis. The linear regression model was best fitted to estimate the 5th, 50th, and 95th percentile range of liver length at each gestational week. Fetal liver length was gradually increased with GA with fitted equation as follows: Liver length (mm) = 1.61 (GA, week) - 6.75 (r(2) = 0.94, p < 0.001).

Conclusion: A normal reference range of fetal liver length for each GA between 14 and 40 weeks was constructed. This may be a useful tool in assessment for some fetal pathologic conditions, especially when fetal anemia is suspected.