Precocious puberty: Nursing

Puberty is the natural process of sexual maturation where an individual becomes sexually mature. When puberty begins too early, it’s called precocious puberty, and this generally means puberty has started before the age of 8 in those assigned female at birth, and 9 in those assigned male.

Let’s start with some physiology. Puberty is normally under the control of the hypothalamus-pituitary-gonadal axis. It begins when the hypothalamus starts releasing gonadotropin-releasing hormone, or GnRH for short, which travels to the nearby pituitary gland to stimulate the release of two gonadotropin hormones into the blood. These are luteinizing hormone, or LH, and follicle-stimulating hormone, or FSH. These two hormones then signal the ovaries and testes to release sex hormones, mostly estrogen and progesterone in those assigned females at birth, and testosterone in those assigned males at birth.

The increase in sex hormones triggers the maturation of the sex organs and the development of secondary sexual characteristics, including the appearance of facial and pubic hair, breast development, and voice changes, among others. Now, on average, puberty begins around age 10 and a half in those assigned female at birth, and 11 and a half in those assigned male. Generally speaking, puberty lasts for about 4 years, but this can vary quite a lot depending on factors such as race, genetic background, and geographical region.

Okay, precocious puberty can occur because of central factors that involve the brain, hypothalamus, and pituitary gland; or because of peripheral causes that involve the ovaries, testicles, or adrenal glands. So, common causes of central precocious puberty include brain tumors or brain trauma. Most of the time, however, there’s no identifiable cause, and it’s simply called idiopathic central precocious puberty, and it’s influenced by factors like when a parent began puberty, as well as an individual's weight.

Conversely, causes of peripheral precocious puberty include sex hormone-secreting ovarian or testicular tumors, genetic conditions like McCune-Albright syndrome, which causes excessive endocrine stimulation and hormone secretion; hypothyroidism or congenital adrenal hyperplasia; or use of exogenous sex hormones from medications and creams.

Finally, risk factors for precocious puberty include being assigned female at birth, black race, obesity, as well as family history of precocious puberty.

Okay, now let’s discuss the pathology of precocious puberty. Central precocious puberty results from early maturation of the hypothalamic-pituitary-gonadal axis. This causes the hypothalamus to release GnRH prematurely, which stimulates the pituitary gland to release LH and FSH. These hormones then stimulate the gonads to release sex hormones, which ultimately leads to precocious puberty.

On the flip side, peripheral precocious puberty results from the overproduction of sex hormones from the gonads or the adrenal glands; as well as dysfunction of other endocrine glands, without the premature release of GnRH from the hypothalamus.