Shepard Estimated Fetal Weight Calculator

Overview

Estimates fetal weight from biparietal diameter and abdominal circumference using the Shepard equation.

Clinical Significance

Estimated fetal weight should be interpreted alongside gestational age, growth trajectory and ultrasound quality.

When to Use

• Use as structured clinical decision support when the required data are available and reliable.

How It Is Calculated

• The displayed variables are combined using the published equation, decision rule or weighted point system.

Interpretation

• Estimated fetal weight should be interpreted alongside gestational age, growth trajectory and ultrasound quality.

Worked Example

Enter verified patient data in the displayed units; MedicalC applies the published model.

Limitations

• Risk and classification tools can be misapplied outside their validated population.
• Missing, estimated or non-contemporaneous data may materially change the result.

Clinical Pearls

• Document the inputs, units, date and clinical setting with the result.
• Use serial scores only when the same instrument and measurement method are used consistently.

Common Mistakes

• Using the tool without confirming entry criteria.
• Using approximate or incorrectly converted values.
• Treating a prognostic score as a standalone treatment decision.

References

1. Shepard MJ et al. Am J Obstet Gynecol. 1982;142:47-54. — Primary or supporting reference for the implemented model.