Precocious Puberty

What is precocious puberty?

Onset of secondary sexual characteristics before age 8 in girls or before age 9 in boys.

What are the two major types of precocious puberty?

Central (GnRH-dependent) and Peripheral (GnRH-independent).

What is central precocious puberty (CPP)?

Early activation of the hypothalamic–pituitary–gonadal axis causing premature puberty.

What is peripheral precocious puberty (PPP)?

Puberty caused by excess sex hormones independent of GnRH activation.

What is the most common cause of central precocious puberty?

Idiopathic, especially in girls.

What are pathologic causes of central precocious puberty?

• CNS tumors

• CNS injury

• Hydrocephalus

• Radiation

• Congenital brain malformations.

What are common causes of peripheral precocious puberty?

• Ovarian cysts

• Ovarian tumors

• Testicular tumors

• Congenital adrenal hyperplasia

• Adrenal tumors

• Exogenous estrogen/testosterone

• McCune-Albright syndrome.

What is the pathophysiology of central precocious puberty?

Early GnRH pulsatile release → LH/FSH activation → gonadal sex hormone production → secondary sexual characteristics.

What is the pathophysiology of peripheral precocious puberty?

Excess estrogen or testosterone from gonads/adrenals → secondary sexual characteristics without GnRH activation.

What are symptoms of precocious puberty?

• Breast development

• Testicular enlargement

• Pubic hair

• Body odor

• Acne

• Growth acceleration.

What physical exam finding distinguishes central from peripheral precocious puberty?

Testicular enlargement suggests central

What growth pattern is seen in precocious puberty?

Accelerated growth velocity with advanced bone age.

What labs help differentiate central vs peripheral precocious puberty?

• LH

• FSH

• Estradiol/testosterone

• DHEA-S

• 17-hydroxyprogesterone.

What LH level suggests central precocious puberty?

Elevated basal LH or LH rise after GnRH stimulation.

What LH level suggests peripheral precocious puberty?

Low LH that does not rise after GnRH stimulation.

What imaging is required in central precocious puberty?

Brain MRI, especially in boys or girls <6 years.

What imaging is required in peripheral precocious puberty?

• Pelvic ultrasound

• Testicular ultrasound

• Adrenal imaging depending on suspected source.

What bone age finding supports precocious puberty?

Advanced bone age compared to chronological age.

What are diagnostic criteria for central precocious puberty?

• Early secondary sexual characteristics

• Elevated LH/FSH

• Positive GnRH stimulation test

• Advanced bone age.

What are diagnostic criteria for peripheral precocious puberty?

• Early secondary sexual characteristics

• Low LH/FSH

• No response to GnRH

• Elevated sex hormones from peripheral source.

What are treatment goals in precocious puberty?

• Halt premature sexual development

• Preserve adult height

• Treat underlying cause.

What is first-line treatment for central precocious puberty?

GnRH agonists (leuprolide).

How do GnRH agonists treat central precocious puberty?

Continuous GnRH suppresses LH/FSH release → halts puberty progression.

What is treatment for peripheral precocious puberty?

Treat underlying cause:

• Remove tumors

• Manage CAH

• Stop exogenous hormones

• Aromatase inhibitors in select cases.

What non-pharmacologic measures support management?

• Growth monitoring

• Psychosocial support

• Regular follow-up with endocrinology.

What are complications of untreated precocious puberty?

• Short adult height

• Psychosocial stress

• Early menarche

• Advanced bone maturation.

What follow-up is required in precocious puberty?

• Growth velocity

• Bone age

• Pubertal staging

• Hormone levels

• Treatment response

What preventive measures reduce risk of peripheral precocious puberty?

Avoid exogenous hormone exposure (creams, supplements).

What conditions mimic precocious puberty?

• Premature thelarche

• Premature adrenarche

• Obesity-related early puberty

• Hypothyroidism.

What feature helps differentiate premature thelarche from precocious puberty?

Isolated breast development with normal growth** and **normal bone age.

What feature helps differentiate premature adrenarche from precocious puberty?

Pubic hair and body odor without breast development or testicular enlargement.

What feature helps differentiate hypothyroidism from precocious puberty?

Hypothyroidism may cause delayed bone age, not advanced bone age.