Ultrasound weight estimation of large fetuses.

• Objective: To compare the accuracy of fetal weight estimation in large fetuses using four ultrasound formulas. Design: Prospective comparative study. Setting: University Hospital, Lund, Sweden. Population: Large-for-gestational age fetuses (n = 114) at a routine ultrasound examination in the third trimester. Methods: Persson & Weldner two-dimensional formula was compared with Hart et al. two-dimensional formula incorporating maternal weight, and Lee et al. and Lindell & Maršál three-dimensional formulas. The formulas are based on two-dimensional measurements of fetal head, abdomen, and femur, and three-dimensional volumetry of fetal abdomen and thigh. Main outcome measure: Accuracy in detection of fetuses with birth weight >4 000 g and >4 500 g. Results: For fetuses >4 000 g, Lindell & Maršál three-dimensional formula showed significantly smaller mean absolute percentage error than Persson & Weldner two-dimensional, and Lee et al. three-dimensional formulas (p = 0.04 and p < 0.001, respectively). No significant difference between Lindell & Maršál three-dimensional and Hart et al. two-dimensional formulas was found. Receiver operating characteristic curve showed higher detection rate for fetuses with birth weight >4 500 g using three-dimensional compared to two-dimensional technique. The best performance in detecting fetuses with birth weight >4 500 g showed Lindell & Maršál three-dimensional formula: for estimated fetal weight >4 300 g the detection rate was 93% and false positive rate 38%. Conclusion: The ability to detect macrosomic fetuses in a preselected high-risk group was higher using the fetal weight estimation with a three-dimensional compared to a two-dimensional ultrasound technique, with or without maternal weight included.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Reproduktionsmedicin och gynekologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Obstetrics, Gynaecology and Reproductive Medicine (hsv//eng)

Publication and Content Type

art (subject category)

ref (subject category)