Soft tissue volume of upper arm in predicting small-for-gestational-age fetuses using three-dimensional ultrasound

To assess the value of fetal soft tissue volume (STV) of the upper arm in predicting small-for-gestational-age (SGA) fetuses using three-dimensional (3D) ultrasound (US).

We used 3D US to test the accuracy of fetal STV of the upper arm measurement in predicting SGA in a prospective cross-sectional study.

Fetal STV of the upper arm assessed by 3D US can differentiate SGA fetuses from appropriate-for-gestational-age (AGA) fetuses. Using the 5th percentile as the cutoff, the sensitivity of fetal upper arm STV in predicting SGA fetuses was 84.1%, specificity, 93.4%, positive predictive value, 71.1%, negative predictive value, 96.8%, and overall accuracy, 91.9%. In addition, the diagnostic accuracy of fetal arm STV was better than that of the biparietal diameter, abdominal circumference, and femur length.

Fetal STV of upper arm assessment by 3D US is a novel method to predict SGA fetuses.