mid parental percentile

Last reviewed 01/2018

The mid parental percentile calculates the expected height of an individual given their parents' heights.

The first stage is to take a mean of the parental heights.

The mid parental height is calculated in males, by adding 7cm to the mean of parental heights; in females by subtracting 7cm. This gives the height expected at 18 years for the child, and this can be plotted on the percentile chart to predict the child's height at the appropriate age. This can normally vary by two standard deviations, or 5cm each way (1).

This measurement aids distinction between genetic and constitutional growth disturbances.

This calculation is not appropriate if either natural parent is not of normal stature.

Reference:

  • Cole TJ (1994). Do growth chart centiles need a facelift, BMJ, 308, 641-2.