Omar Method EFW Calculator

Measure SFH from the highest point of the uterine fundus, not necessarily midline. Ensure bladder is empty. Measurements should be taken within 5 days of delivery. Round to nearest cm.

• Gestational age 37 to 41+6 weeks
• BMI less than 35
• Live singleton fetus in longitudinal lie, vertex presentation
• Normal liquor, intact membranes
• Head 4/5 or 5/5 above the brim

• No early ultrasound or uncertain dates
• BMI greater than 35
• Polyhydramnios, oligohydramnios, fibroids, ovarian cysts
• Abnormal lie or malpresentation
• Multiple pregnancies
• Intrauterine deaths
• Congenital anomalies
• Rupture of membranes
• Patients greater than 4 cm dilated
• Hypertension, gestational diabetes

In the study population:

Simple method
68.7% within 10% of birth weight

Complex method
72.5% within 10% of birth weight

Based on a South African term pregnancy cohort.
Further validation studies are required before widespread clinical use.

This calculator is saved as a single HTML file and can be opened without internet access on most phones, tablets, and computers. Save the file to your device and open it in a browser. The written simple formula above can also be used manually if the calculator does not load.

This is a novel calculator developed from MMed research. It is not officially endorsed by any medical body. Use is for research or educational purposes only. Clinical decisions should not rely solely on this tool.