Predicting birth weight in fetuses with gastroschisis

Area of Science:

• Perinatology
• Fetal Medicine
• Medical Imaging

Background:

• Gastroschisis is a congenital defect with potential impacts on fetal growth.
• Accurate estimation of fetal birth weight (BW) is crucial for managing pregnancies complicated by gastroschisis.

Purpose of the Study:

• To evaluate the accuracy of common ultrasound formulas for estimating fetal birth weight in cases of gastroschisis.
• To determine the most reliable formula for predicting BW in fetuses diagnosed with gastroschisis.

Main Methods:

• Retrospective review of 111 inborn gastroschisis cases (2007-2012) with ultrasound within 21 days of delivery.
• Evaluation of five ultrasound formulas: Hadlock 1 & 2, Shepard, Honarvar, and Siemer.
• Analysis using Pearson's correlation, mean difference, percent error, and Bland-Altman plots; assessment of intrauterine growth restriction (IUGR) diagnostic performance.

Main Results:

• The Hadlock (1) formula demonstrated the best performance with the highest correlation (r=0.81), lowest mean difference (8±306g), and lowest mean percent error (1.4±13%).
• Honarvar and Siemer formulas showed significantly worse accuracy compared to Hadlock 1.
• Hadlock (1) and (2) formulas achieved 80% sensitivity and 91% negative predictive value for diagnosing IUGR.

Conclusions:

• The Hadlock (1) and (2) ultrasound formulas are the most accurate for estimating birth weight in fetuses with gastroschisis.
• These formulas remain effective despite the presence of abdominal circumference measurements, which might be affected by gastroschisis.
• The Hadlock formulas are also reliable for the ultrasound diagnosis of intrauterine growth restriction in this population.