Tested on Gulf Medical Boards (DHA, SMLE, MOH & HAAD)
Clinical calculations and diagnostic scoring systems like Hadlock Estimated Fetal Weight (EFW Sonographic Biometry) frequently appear on Prometric exams. Master high-yield clinical vignettes with instant AI-powered pathophysiology rationales.
What is the Hadlock Estimated Fetal Weight (EFW Sonographic Biometry)?
The Hadlock Estimated Fetal Weight (EFW Sonographic Biometry) is an evidence-based clinical decision rule engineered to quantify diagnostic probability, stratify clinical severity, and guide therapeutic decision-making in obstetrics & gynecology practice. Implements Hadlock’s validated 4-parameter sonographic regression formula using Biparietal Diameter (BPD), Head Circumference (HC), Abdominal Circumference (AC), and Femur Length (FL) to determine Estimated Fetal Weight (EFW) and evaluate for intrauterine growth restriction (IUGR) or macrosomia. Clinical scoring tools like Hadlock Estimated Fetal Weight (EFW Sonographic Biometry) are essential in acute and outpatient management, enabling clinicians to objectively differentiate between low-risk candidates suitable for conservative therapy and high-risk patients requiring urgent interventions. Verified against current 2026 clinical standards, this tool is extensively tested on Gulf health authority licensing exams including DHA (Dubai), SMLE (Saudi Arabia), MOH, HAAD/DOH (Abu Dhabi), OMSB (Oman), and QCHP (Qatar).
💡Clinical Pearls & Diagnostic Utility
The global standard obstetric sonography algorithm embedded in hospital ultrasound machines worldwide for fetal biometric weight assessment.
Formula & Calculation Parameters
The mathematical equation and clinical variables required to calculate Hadlock Estimated Fetal Weight (EFW Sonographic Biometry):
Score Interpretation & Clinical Stratification
| Score Range | Clinical Interpretation | Risk Tier |
|---|---|---|
| ≤ 2499 | Low Birth Weight / FGR Consideration (< 2,500g) | yellow |
| 2500 – 3999 | Appropriate for Gestational Age (2,500g - 3,999g) | green |
| ≥ 4000 | Macrosomia Range (≥ 4,000g) | red |
When to Exercise Caution
Ultrasound EFW typically exhibits an inherent error margin of ± 10% to 15%; maternal obesity, oligohydramnios, and multiple gestation may reduce precision.
Clinical Review Board
Dr. Muhammad Nouman, MBBS
Capital Medical University | PMDC Reg No: 117744-P
Clinical Audit Status
✓ Verified for 2026 Guidelines
Last updated: 2026-08-08
Peer-Reviewed Medical Literature
- •Hadlock FP, et al. Estimation of fetal weight with the use of head, body, and femur measurements—a prospective study. Am J Obstet Gynecol. 1985;151(3):333-337.
- •ACOG Practice Bulletin No. 216: Macrosomia. Obstet Gynecol. 2020;135(1):e18-e35.
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