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You Can Predict Your Newborn's Weight

Equation Just as Good as Ultrasound, Easier to Use

continued...

Pointers for performing the calculations:

  • Perform all multiplications before the additions.
  • Gestational age is the stage of your pregnancy in days, or days since the onset of your last normal menstrual period plus 14.
  • For fetal sex, use 1 for a boy, -1 for a girl, or 0 if sex is unknown.
  • For mother's height, inches multiplied by 2.54 gives you centimeters.
  • For the mother's weight, pounds divided by 2.2 gives you kilograms.
  • For the baby's birth weight, take the number from your calculation and divide by 453 to get your baby's estimated weight in pounds.

If you don't have a thing for math, you might want to show this to your obstetrician. -->

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