Objectives: To assess the contribution of sonographically measured parameters, namely head circumference, biparietal diameter, abdominal circumference, and femur length, to fetal weight estimation formulas. Methods: The Sobol' method is employed for the global sensitivity analysis of the biometric parameters. Results: The Sobol' sensitivity indices for the parameters of 32 known formulas are presented and discussed. Conclusions: Depending on the formula, the indices of some parameters show substantial fluctuations, while others are insignificant for fetal weight estimation.

The authors have declared no competing interest.

This study did not receive any funding.

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