THE ACCURACY OF ULTRASOUND ESTIMATION OF FETAL WEIGHT IN COMPARISON TO BIRTH WEIGHT
DOI:
https://doi.org/10.71000/fgh82j52Keywords:
Birth Weight, Estimation Techniques, Fetal Weight, Pregnancy, Ultrasonography, Weight Prediction Error, Women’s HealthAbstract
Background: Accurate estimation of fetal weight is a crucial component of obstetric care, influencing decisions related to delivery planning, mode of birth, and management of potential complications. Errors in estimation may result in inappropriate clinical interventions, posing risks to both maternal and neonatal health. Ultrasonography is widely used due to its non-invasive nature and accessibility; however, its precision varies based on multiple clinical and technical factors, necessitating evaluation in diverse healthcare settings.
Objective: To assess the accuracy of fetal weight estimation using ultrasonography in comparison to actual birth weight.
Methods: This observational study was conducted at the Armed Forces Institute of Radiology, Rawalpindi, Pakistan, from September 2023 to February 2024. A total of 139 postpartum women were included through convenience sampling. All participants had complete data on both ultrasound-estimated fetal weight (EFW) and actual birth weight (ABW). Women with multiple gestations, major fetal anomalies, or deliveries outside the facility were excluded. Fetal biometry was performed using standardized equipment and protocols, applying the Hadlock 4 formula based on BPD, HC, AC, and FL. Birth weights were recorded within 10 minutes post-delivery. Data analysis was performed using SPSS version 26.0.
Results: The mean EFW was 2752.68 ± 282.95 grams, while the mean ABW was 2819.30 ± 397.31 grams. A statistically significant difference was observed between the two values (p = 0.000). The mean absolute error in estimation was 193.95 ± 248.08 grams. Underestimation occurred in 44.6% of cases, overestimation in 28.8%, and accurate estimation within ±10% was observed in only 26.6% of the sample.
Conclusion: Ultrasonographic estimation of fetal weight tends to underestimate actual birth weight and should be interpreted alongside clinical findings to guide appropriate obstetric decision-making.
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Copyright (c) 2025 Saba Kanwal, Khawaja Muhammad Baqir Hussain, Ayesha Niaz, Koukab Javed, Aliya Halim, Sara Khan (Author)
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