Fetal Weight Calculator - Hadlock Formula
Estimate fetal weight from ultrasound measurements (Hadlock formula).
Estimated fetal weight
151,79 kg
151.795 g
Grams
Hadlock formula. Estimate with margin of error; your OB-GYN handles the real follow-up.
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Frequently asked questions
What measurements does the Hadlock formula need?
Biparietal diameter (BPD), head circumference (HC) and femur length (FL), all in centimeters, as reported on the ultrasound.
How accurate is the estimated fetal weight?
The estimate has a ±10-15% margin of error. The real weight is only known at birth; third-trimester ultrasounds are approximate.
Fetal Weight and Why It Matters
The estimated fetal weight helps the OB-GYN monitor the baby growth. The Hadlock formula combines several ultrasound measurements for a more reliable estimate than a single one. This calculation is informational: your specialist always handles your pregnancy follow-up.