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Fetal Growth Calculator - Definitions

Definitions

  • Gestational Age:
    Age of the pregnancy, in completed weeks and days   
  • Biparietal Diameter (BPD):
    Distance between the two parietal bones of the fetal skull (outer to inner), in millimeters   
  • Head Circumference:
    Measurement of the fetal head at its widest, in millimeters   
  • Abdominal Circumference: Measurement of the fetal abdomen, in millimeters   
  • Femur Length: Length of the fetal thigh bone, in millimeters   
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Illustration of the four measurements on a baby’s body: femur length, abdominal circumference, head circumference, and biparietal diameter.