An evaluation of human chorionic gonadotrophin (HCG) therapy in boys with delayed puberty

Fifty male patients with delayed pubertal development (chronological age 13.3-17.6 years; bone age 9.5-14 years) were treated with human chorionic gonadotrophin (HCG) 1500-2000 units twice weekly for six months to promote pubertal development and accelerate growth. Response was compared with an untreated control group of 28 patients (chronological age 12.5-17.5 years; bone age 7.0-13.0 years). Forty-four of 46 patients in the treatment group achieved genital stage 3 or 4 by the end of therapy; untreated patients either remained unchanged or advanced only one genital stage during this period. Testicular volumes increased from a median 4.5 ml (range 1-12 ml) to 9 ml (range 3.5-15 ml) in the treated patients. In untreated patients testicular volume increased from 6.0 ml (range 2-10 ml) to 9.5 ml (range 4-20 ml) over the same period. In patients initially growing at less than 7.0 cm/year height velocity increased from 3.9 cm/year (range 0-6.6 cm/year) to 12.7 cm/year (range 8.9-16.8 cm/year) during therapy, falling to 6.0 cm/year (range 0-12 cm/year) in the three-month period immediately following treatment. Patients initially growing at greater than 7.0 cm/year showed variable responses to treatment. Prepubertal patients showed the greatest acceleration in annual growth compared with controls. Treated patients with an initial skeletal age less than 12.0 years showed either a final height (when known) which was less than initially predicted or a significant reduction in predicted height following treatment. Skeletal age greater than 12.0 years was not associated with excess osseous maturation. In conclusion, pre-pubertal children growing at less than 7 cm/year show the greatest benefit from HCG therapy, but final height may be prejudiced if initial bone age is less than 12 years.