Olsen 2015 BMI Calculator for Preterm Infants

Uses the 2015 Olsen BMI curves to report percentiles and Z-scores.

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Today is Wednesday, June 26th, 2019

Parameters for BMI Calculation

Growth metrics on analysis date
Gender Male Female
Gestational age
Weight (grams)
Length (cm)

Last menstrual period
Due date

Date of birth
Gestation at birth

Analysis date
Age in days on date
Day of life on date

Reset form

Tips and Tricks

  • Enter the bare minimum information
    • can enter just gender, gestational age, and growth metrics, without dates, if desired
    • if only a gestational age is entered, the 50th percentile values will be displayed
    • if any dates are entered, all other dates will be deduced, if possible
  • Gestational age, enter in the form of ## #/7; e.g., 30 3/7 for 30 weeks and 3 days gestation
  • Weight: grams are assumed. To enter pounds and ounces, enter #-#; e.g., 8-4 for 8 pounds and 4 ounces
  • Length: cm are assumed. To enter inches, enter #"; e.g., 20" for 20 inches

Based on