size and ethnicity, mom's health and age, and how much mom gained during pregnancy. other factors include the baby's health and gestational age ( premature babies are often smaller), whether the baby is a boy or girl, a first baby or later baby, or a singleton or multiple . being ...
There's no one number to define a normal baby head circumference at a given age, but there are charts that provide ranges. These charts give the average head circumference for a boy or girl at a given age, and they allow your baby's doctor to compare your baby's head size with the ...