Puberty and Precocious Puberty

Here’s the RoshReview Question of the Week!

A 30-year-old woman brings her 7-year-old daughter for consultation. She noted the presence of clinical signs of puberty and is worried that this might be occurring too early for her age. Which of the following distinguishes central precocious puberty from peripheral precocity?

• Adrenarche

• Basal luteinizing hormone

• Bone age

• Secondary sexual characteristics

Check your answer by clicking the links above!

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What is puberty? 

• Physical process of maturation from child to adult that is capable of sexual reproduction 

• Also process of cognitive and psychosocial maturation

• Two main areas: 

  • Gonadarche - activation of the gonads by pituitary hormones (FSH/LH) 

  • Adrenarche - increase in production of androgens in the adrenal cortex 

• Cause

  • Triggered by hypothalamic activation and production of GnRH in pulsatile fashion that leads to FSH and LH production 

  • Not completely understood what causes the hypothalamus to begin this process

    • Thought to be governed by many factors like general health, nutrition, genetic factors, and other environmental cues 

    • Interesting to think about since the age of menarche in Europe decreased from 17.5 to 12.5-13 years in the last few centuries 

• Timing of puberty

  • On average, girls begin puberty at age 10-11

• One other note 

  • Puberty can be a time of emotional distress 

  • Not only are patients usually preteens or teens, with multiple societal and home pressures (school, friends, parents, etc), they are also experiencing significant changes in their bodies 

  • Child psych studies have shown that clinical symptomatology for previously diagnosed psychiatric disorders increase steeply when they reach puberty, and for some, this is the first onset of psychological symptoms 

  • So for these patients, important to follow them and work closely with your peds colleagues 

What are the different components of puberty? 

Mnemonic: boobs, pubes, spurt, squirt - Defined by Marshall and Tanner in 1970 (yes, that Tanner!) 

• Thelarche - breast development 

  • Usually first physical sign of puberty is breast buds 

• Pubarche (adrenarche?) - growth of pubic hair, usually follows a few months after breast development begins 

  • Thelarche and pubarche form the basis for Tanner staging in girls: (image source)

• Growth spurt  

• Menarche - getting your first period; the average age in the US is around age 12

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So what is precocious puberty? 

• More on timing of puberty:

  • Usually, puberty begins around the age of 10

    • However, there is a wide range, and can be anywhere from age of 8-13. Remember, puberty is NOT just beginning of menstruation! 

    • It can be evidence of breast development, pubic hair growth, etc.  

  • Precocious puberty is evidence of puberty that starts 2.5 SD earlier than the populational norm

    • Classically, it’s been defined as breast budding before the age of 8 in girls, though there is some racial differences in the literature that range somewhere between the ages of 7-8, and there is an increasing trend of earlier puberty in the US.

    • For simplicity’s sake, we will use the age of 8 as our cut off – at least when we should start THINKING that there maybe signs of precocious puberty 

• Incidence and Risks

  • This is a little difficult to assess 

    • You might expect it to be 2% because we are using 2 to 2.5 standard deviations from the general population in the US 

    • But… in a population-based study, breast and/or pubic hair development at age 8 occurred in 48% of Black females and 15% of white females in the US. At age 7, this was 27% and 7% 

    • But if you look at a different population, the results are drastically different 

    • So… definition of precocious puberty is overall problematic, especially in female children. Instead, need to take into other factors as well, such as obesity

• Strong predominance for females (approximately 87% of those evaluated in one study) 

• In about 80% of girls with precocious puberty, it will be idiopathic 

Why do we care about precocious puberty? 

•  Psychosocial reasons

  • Early menarche is often associated with earlier timing of sexual debut 

  • Increased risk of teenage pregnancy and sexually transmitted infections (HPV) 

  • Children may not be prepared for the implications of puberty and sexual maturation 

• Other implications/health 

  • Early closing of the epiphyseal plates can lead to shorter stature 

  • Increased risk of breast cancer, heart disease, diabetes, and all-cause mortality 

What causes precocious puberty? 

• Central precocious puberty (CPP)

  • Definition: Early maturation of the HPO axis … what causes it? 

  • Idiopathic 

    • In about 80-90% of females, but only 25% of males 

  • Central nervous system lesions

    • Hypothalamic hamartomas 

    • Other CNS tumors 

    • Cranial radiation 

• Peripheral precocity 

  • Usuall due to excess secretion of sex hormone 

  • Ovarian tumors - overall rare, but can be from granulosa cell tumors. Rarely, sertoli/Leydig cell tumors can cause androgenization 

  • Primary hypothyroidism 

    • Severe, long-standing hypothyroidism can occasional cause precocious puberty 

    • Thought is due to cross-reactivity and stimulation of FSH receptor by high levels of TSH (same alpha sub unit) 

  • Exogenous chemicals/sex steroids  

  • Adrenal tumors 

  • Congenital adrenal hyperplasia - though these patients may present as early as infancy 

  • McCune-Albright Syndrome

    • Super rare → triad of peripheral precocious puberty, irregular cafe-au-lait spots (coast of Maine), and fibrous dysplasia of the bone  

How do we work this up? 

• As always, history and physical 

  • If you suspect, you should ask patient and guardian 

  • When did they first notice changes, and how long has this been going on for? 

  • How quickly has this been progressing? 

    • Has this been occurring in the last year, and there has been very quick development of breast tissue with rapid onset of menstruation? More concern for peripheral source or tumor 

    • What about growth? Rapid growth may suggest CPP. Slower growth might signal benign or idiopathic cause 

  • Any changes with headaches, vision changes (suggests CNS tumor) 

  • Possible exposure to exogenous chemicals? Is mom on hormone replacement therapy and using estrace gel or cream? Did the child somehow get into it? 

  • Physical exam 

    • Height, weight, and height velocity (not something we usually do, so this might be best evaluated by the patient’s pediatrician!) 

    • Look for signs of McCune Albright - are there cafe au lait spots? 

    • Pubertal staging (Tanner Staging) 

• Testing to order 

  • Bone radiograph - we don’t generally do this, so maybe think of referring to pediatric endocrinology, especially for follow up

    • Usually a hand X-ray to look at the growth plates in the metacarpals, wrist, etc 

    • Can assess for advance in bone age or premature closure of the growth plates 

  • FSH, LH, estradiol, and testosterone 

    • Elevated estradiol with suppression of FSH or LH is suggestive of peripheral production 

  • Consider getting a brain MRI to r/o central lesion 

  • Pelvic ultrasound - this will allow us to see peripheral tumors 

  • Specifically in patients with precocious pubarche (ie. pubic hair growth, axillary hair growth, but no menarche) 

    • Measurement of adrenal steroids 

    • Early morning 17-OHP, DHEA, testosterone, androstenedione 

• Also refer to pediatric endocrinology! 

• Treatment is based off of the cause - which we won’t cover today, but:

  • Principles of treatment will be based off of child’s age, rate of progression, height velocity, estimated height 

  • Goal of treatment is to allow child to grow to normal adult height and also to relieve psychosocial stress 

  • Usually for children with CPP, can treat with GnRH agonist 

  • Again - usually this is done with pediatric endocrinology, so we will defer further management to them.

    • This episode is designed to help you figure out the initial stages if someone comes to you with this issue!