[Mean fetal growth curve adjustment]

To present the optimum equation of the anthropometric fetal growth curve evaluated by height, weight and head circumference according to sex and gestational age. To find the inflection point of the mentioned curves to get to know the precise moment in which growth velocity is the fastest.

We have used the anthropometry of 25,200 newborns (ages ranging from 25 to 43 weeks). All of them were born in the Neonatology Service of the San Carlos Hospital, Madrid. The statistical method used was to check wether fetal growth fitted a logistic curve. The accuracy of the contrast is based on non-linear regression technics.

We present the tables for newborns (boys and girls) showing mean growth and weight, height and head circumference upper and lower limits, from the 25th to the 43rd gestational week.

Fetal anthropometric growth fits perfectly a logistic curve. Mean growth velocity reduces sooner in girls than in boys. Weight growth velocity reduces later than height and head circumference.