Central Precocious Puberty

Central Precocious Puberty (CPP) is a pubertal disorder that results from the premature activation of the hypothalamic-pituitary-gonadal axis and mimics normal puberty. The approximate incidence is 1:5000 to 10,000 and is more common in girls than boys occurring at a ratio of approximately 10:1. The most common cause in girls is idiopathic CPP, however in boys it is more likely the result of a demonstrable central nervous system lesion. Approximately 20% of boys with CPP have an underlying CNS lesion compared with a rate of 5% for girls.  


Children with CPP need to be thoroughly evaluated by a pediatric endocrinologist. Evaluation may include blood tests for LH, FSH, estradiol, testosterone, thyroid functions and an x-ray for bone age. A stimulation test may be needed to establish the diagnosis. Pelvic ultrasound in girls with CPP shows enlarged ovarian volume and pubertal changes in the uterus. Due to the potential risk of CNS pathology, MRI of brain may be needed. Treatment is generally indicated in cases of CPP in girls younger than 6 years and boys younger than 9 years. The decision to treat is difficult in girls with CPP between the ages of 6 to 8 years. Most common indications for therapy include poor predicted adult height, rapid advancement of puberty or psychosocial concerns. Untreated precious puberty leads to rapid progression in bone age with premature closure of growth plates and adult short stature.  Children with precocious puberty may also be at increased risk for behavioral difficulties, psychological problems, and impaired peer relations.

CPP is treated by chronic administration of a synthetic GnRH agonist in the form of depot injections or implants. The treatment is discontinued at a bone age of 12 to 13 years after which puberty progresses normally.