Check Fetal Growth

How to interpret an EFW percentile

An EFW percentile shows the relative position of an entered value within the selected reference at the same gestational age. It is not a diagnosis or a normal-abnormal judgment.

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What a percentile means

A percentile describes where the entered value sits within the selected reference. It is not a normal or abnormal judgment, and it should not replace clinical review.

Selected data stays separate

WHO, INTERGROWTH-21st, Korean, Japanese, and NICHD datasets are not mixed or combined. The calculator uses the percentile values from the selected reference only.

Which reference should I choose?

Use the reference your clinician or ultrasound report expects when one is specified. If you compare another source, read it as a separate reference shown as selected.

Is this a medical diagnosis?

No. The result is a reference percentile only. It does not diagnose growth restriction, macrosomia, placental function, or future outcome.