Accuracy of Ultrasound Determination of Estimated Fetal Weight in Small for Gestational Age Pregnancies
Abstract
Background: Approximately half of small for gestational age (SGA) cases are due to maternal or fetal pathology, and may result in significant neonatal morbidity and mortality. The estimated fetal weight (EFW) measurement is the cornerstone of ultrasonographic findings when diagnosing and managing SGA pregnancies. The objective of present study was to determine the ultrasound accuracy of EFW in SGA pregnancies and compare accuracy in appropriate for gestational age pregnancy (AGA) and SGA pregnancy. Method: In this prospective randomized observational study, fifty pregnant women at term with appropriate for gestational age pregnancy and fifty other women at term with small for gestational age pregnancy had ultrasonic estimation of fetal weight performed within a week of delivery. Results: A total of 100 cases (50 SGA and 50 AGA) were analyzed. The newborn birth weight range was 1500 gm to 3500 gm. The study found no significant difference between adjusted ultrasound EFW calculated using Hadlocks formula and actual birth weight of the neonate in both AGA and SGA pregnancies (p˃0.05). The mean absolute percent error for the entire sample was 6.6096. Mean absolute error for appropriate and small for gestational age pregnancies was 6.16889 and 7.05031 respectively, (p˃0.05). Percentage of overestimation of fetal weight was more in SGA pregnancy (65%) as compared to AGA pregnancy (54%), (p˃0.05). Conclusion : In clinically suspected SGA pregnancies ultrasound estimation of fetal weight by Hadlocks formula are a valid estimate of actual birth weight and the preferred mode of diagnosis. Accuracy of ultrasound estimation of fetal weight in SGA pregnancies is comparable to accuracy of estimation of fetal weight in AGA pregnancies.Downloads
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