Delayed puberty

Many patients with delayed puberty are detected or seek medical help because of slow growth rather than slow pubertal development, as well as due to concerns that puberty has not started. The slow growth results from delayed sex-hormone secretion and is only rarely due to other causes such as growth hormone deficiency.

Although there are currently no recommended screening programmes to detect children with a delay in pubertal development, short stature and a poor growth velocity at secondary school entry should warrant review by a family practitioner. Current interventions are usually directed at speeding up both growth and the pubertal process.

Accurate measurements, using correct age- and sex-specific growth charts, are mandatory. Care must be taken to plot the height and weight based on the child's actual chronological age.

Growth is strongly related to the genetic potential. The target or mid-parental height is calculated as follows:

• Girl = ([height of mother in cm + height of father in cm]/2) - 7 cm

• Boy = ([height of mother in cm + height of father in cm]/2) + 7 cm

Growth velocity determines the change in height over time. It is calculated as the difference in height on two different occasions annualised over 1 year. Growth velocities depend on age and pubertal status. Height that plots stably along a given percentile on the growth chart reflects normal growth velocity. Crossing percentiles in a downward direction reflects a poor growth velocity.