This version was machine-translated from German and has not been medically reviewed. The authoritative version is the German version.
Fenton 2013 Growth Calculator / Fenton 2013 Growth Calculator
Weight, length, head circumference by postmenstrual age; expected weight gain
About this calculator
Percentiles and z-score of weight, length and head circumference according to Fenton 2013 (22–50 weeks postmenstrual) with integrated gestational age calculator, SGA/AGA/LGA classification at birth and the weekly weight gain needed to maintain the current percentile.
Postmenstrual age = gestational age at birth + age since birth. For classification at birth (SGA/AGA/LGA), completed weeks are customary; here the curves are interpolated to the day.
Frequently asked questions
How is postmenstrual age calculated?
Postmenstrual age = gestational age at birth + age since birth. A child born at 30+2 weeks who is 20 days old has a postmenstrual age of 33+1 weeks. The calculator determines it from the dates of birth and measurement or accepts it directly.
What do SGA, AGA and LGA mean?
At birth, a weight below P10 counts as SGA (small for gestational age), from P90 as LGA (large for gestational age), and in between as AGA. Fenton recommends completed weeks for this classification.
Where do the Fenton 2013 curve data come from?
The LMS parameters come from the official Excel calculator of the University of Calgary (Fenton & Kim, BMC Pediatrics 2013), License CC BY-NC-ND 4.0. kinderarzt.org uses them non-commercially.
How much should a preterm infant gain per week?
The calculator shows the gain needed to maintain the current z-score for one week. In stable preterm infants, 15–20 g/kg/day is usual; the exact target is a clinical decision.