Precocious Puberty in Girls

Key Features

• Defined as pubertal development occurring below the age limit set for normal onset of puberty

• More common in girls than in boys

• Many girls showing signs of puberty between 6 and 8 years of age have a benign, slowly progressing form that requires no intervention

• Age of pubertal onset may be advanced by obesity

• Central precocious puberty in girls is generally idiopathic but may be secondary to a central nervous system (CNS) abnormalities, including but not limited to

  • Hypothalamic hamartomas

  • CNS tumors

  • Cranial irradiation

  • Hydrocephalus

  • Trauma

• Peripheral precocious puberty (GnRH-independent)

  • Occurs independent of gonadotropin secretion

  • Can be caused by ovarian or adrenal tumors, ovarian cysts, late-onset congenital adrenal hyperplasia, McCune-Albright syndrome, or exposure to exogenous estrogen

Clinical Findings

• Usually starts with breast development followed by pubic hair growth and menarche

• Girls with ovarian cysts or tumors generally have signs of estrogen excess such as breast development and possibly vaginal bleeding

• Adrenal tumors and congenital adrenal hyperplasia produce signs of androgen excess which include pubic hair, axillary hair, acne, and increased body odor

• Children with precocious puberty usually have accelerated growth and skeletal maturation, and may temporarily be tall for age

Diagnosis

• If the bone age is advanced, further laboratory evaluation is warranted

• In girls with an ovarian cyst or tumor, estradiol levels will be markedly elevated

• In central precocious puberty,

  • Random follicle-stimulating hormone (FSH) and luteinizing hormone (LH) concentrations may still be in the prepubertal range

  • If so, documentation of the maturity of the hypothalamic-pituitary axis depends on demonstrating a pubertal LH response after stimulation with a GnRH agonist

• In peripheral precocious puberty, the LH response to GnRH stimulation is suppressed by feedback inhibition of the hypothalamic-pituitary axis by the autonomously secreted gonadal steroids

• In girls with pubic or axillary hair but no breast development, androgen levels (testosterone, androstenedione, dehydroepiandrosterone-sulfate) and 17-hydroxyprogesterone should be measured

• When a diagnosis of central precocious puberty is made, an MRI of the brain should be done to evaluate for CNS lesions

• When laboratory test results suggest peripheral precocious puberty, an ultrasound of the ovaries and/or adrenal gland may be indicated

Treatment

• Two most common GnRH analogs that downregulate pituitary GnRH receptors and thus decrease gonadotropin secretion are leuprolide, which is given as a monthly intramuscular injection, and histrelin subdermal implant, which is replaced annually

• In a girl with an ovarian cyst, intervention is generally not necessary, as the cyst usually regresses spontaneously

• Surgical resection and possibly chemotherapy are indicated for the rare adrenal or ovarian tumor

• Aromatase inhibitors, which block the production of estrogen, may be effective in treating McCune-Albright syndrome

• Attention to the psychological needs of the patient and family is essential