Delayed puberty - causes, symptoms, diagnosis, treatment, pathology

Summary

Puberty marks the transition to sexual maturity, typically delayed if it hasn't begun by age 13 in females and 14 in males. It involves the hypothalamic-pituitary-gonadal axis, which controls sexual development and reproduction through hormone release. This process leads to the development of primary and secondary sex characteristics as outlined by the Tanner scale. Delays can be due to hypogonadism, with causes ranging from primary gonadal dysfunction to secondary hormonal imbalances. Constitutional delay is a temporary delay often with genetic roots, not typically resulting in infertility.

Takeaways

• 🕒 Puberty typically begins by age 13 for females and age 14 for males, with later onset considered delayed.
• 🌐 The hypothalamic-pituitary-gonadal axis is crucial for sexual development and reproduction.
• 🔍 Gonadotropin-releasing hormone from the hypothalamus stimulates the pituitary gland to release hormones that act on the gonads.
• 🚹 In males, testosterone is key for sexual organ development and sperm production during puberty.
• 🚺 In females, estrogen and progesterone are produced by the ovaries and regulate the menstrual cycle and egg maturation.
• 🌱 Primary and secondary sex characteristics develop due to sex hormones, with puberty marked by changes like pubic hair and breast development.
• 📊 The Tanner scale outlines the stages of sexual maturity, from pre-puberty to adult contours.
• 🚨 Delayed puberty can indicate hypogonadism, which may lead to infertility if not addressed.
• 🏥 Hypogonadism can be primary (due to gonadal dysfunction) or secondary (due to hypothalamic or pituitary dysfunction).
• 🧬 Constitutional delay is a temporary delay in puberty often linked to genetics and does not typically result in infertility.
• 🩺 Diagnosis of delayed puberty involves comparing development to the Tanner scale, hormone level tests, and medical history.

Q & A

What is the age considered for delayed puberty in females and males?

Puberty is considered delayed if it hasn't started for a female by age 13 and for a male by age 14.

What is the hypothalamic pituitary gonadal axis and its role?

The hypothalamic pituitary gonadal axis is a system of hormonal signaling between the hypothalamus, pituitary gland, and gonads (testes or ovaries) that controls sexual development and reproduction.

What is gonadotropin-releasing hormone and its function?

Gonadotropin-releasing hormone is released into the hypothalamus and stimulates the pituitary gland to release gonadotrophin hormones, luteinizing hormone, and follicle-stimulating hormone.

How do gonadotrophin hormones affect the gonads?

Gonadotrophin hormones stimulate the gonads to produce sex-specific hormones: estrogen and progesterone in females, and testosterone in males.

What are the primary functions of testosterone during male puberty?

Testosterone helps the external sex organs to differentiate into male genitals, causes the testes to descend, and stimulates the production of sperm by the testes.

What are estrogen and progesterone responsible for in females?

Estrogens and progesterone regulate monthly changes to the ovary and uterine wall, promoting egg maturation, ovulation, and changes as part of the menstrual cycle.

What are primary and secondary sex characteristics?

Primary sex characteristics refer to the genitals involved in reproduction, while secondary sex characteristics are sex-specific physical traits not directly involved in reproduction, such as pubic hair and breasts.

What is the Tanner scale and its significance?

The Tanner scale is a set of developmental stages that males and females go through as they develop sex characteristics and become sexually mature, focusing on pubic hair appearance and genital development.

What are the two main causes of hypogonadism?

The two main causes of hypogonadism are primary hypogonadism, caused by dysfunction of the gonads, and secondary hypogonadism, caused by dysfunction of the hypothalamus or pituitary gland.

What is constitutional delay and how does it differ from secondary hypogonadism?

Constitutional delay is a temporary delay in puberty that is not pathologic and is often genetic, differing from secondary hypogonadism in that puberty can still occur naturally at a later age.

How is delayed puberty diagnosed and treated?

Delayed puberty is diagnosed by comparing sexual development with the Tanner scale, blood tests, and medical history. Treatment depends on the cause and may include hormone therapy or infertility treatments.

Outlines

00:00

🌱 The Onset of Puberty and the Hypothalamic-Pituitary-Gonadal Axis

Puberty marks the period when individuals become sexually mature, typically by age 13 in females and 14 in males. It involves the hypothalamic-pituitary-gonadal (HPG) axis, which regulates sexual development and reproduction through hormonal signals between the hypothalamus, pituitary gland, and gonads (testes in males, ovaries in females). The hypothalamus releases gonadotropin-releasing hormone (GnRH) into the portal system, triggering the pituitary gland to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH). These hormones stimulate the gonads to produce sex-specific hormones—testosterone in males and estrogen and progesterone in females. This process initiates the development of primary (genitals) and secondary (pubic hair, breast development) sexual characteristics.

05:02

🧬 Hormonal Changes and Sexual Maturation

During male puberty, LH stimulates Leydig cells in the testes to convert cholesterol into testosterone, aiding in sperm production. In females, LH stimulates theca cells in ovarian follicles to produce androgens, which are converted by granulosa cells into estrogen and progesterone. These hormones regulate egg maturation and the menstrual cycle. The development of secondary sex characteristics, like pubic hair and breast enlargement, follows a predictable pattern measured by the Tanner scale. Puberty delays are considered when sexual maturation hasn't started by age 13 in females and age 14 in males, often due to low gonad activity (hypogonadism), which can result in infertility if unresolved.

🔄 Primary Hypogonadism: Causes and Effects

Primary hypogonadism occurs when the gonads do not produce sufficient sex hormones due to dysfunction. Causes include genetic conditions like Klinefelter or Turner syndrome, trauma, or treatments like radiation or chemotherapy. In this condition, gonadotropin hormone levels are elevated (hypergonadotropic hypogonadism), as the lack of sex hormone production reduces the negative feedback on the hypothalamus. This leads to increased levels of LH and FSH but insufficient production of testosterone in males or estrogen and progesterone in females.

🔄 Secondary Hypogonadism: The Role of the Brain in Delayed Puberty

Secondary hypogonadism is caused by dysfunction in the hypothalamus or pituitary gland, resulting in low levels of gonadotropin hormones (LH and FSH). Causes include tumors, radiation therapy, chronic illnesses, or hormonal imbalances from conditions like prolactinoma or thyroid issues. Secondary hypogonadism is also known as hypogonadotropic hypogonadism because the reduced gonadotropin levels prevent the gonads from functioning properly, delaying or inhibiting puberty.

⏳ Constitutional Delay: A Non-Pathological Puberty Delay

Constitutional delay is a temporary delay in puberty that is not considered pathological. It often runs in families and results in a natural but late onset of puberty, with normal progression once it begins. Unlike secondary hypogonadism, this delay does not usually lead to infertility. The diagnosis is often made by comparing sexual development to the Tanner scale and measuring hormone levels. Treatment may involve hormone therapy, particularly in cases where an underlying medical condition is the cause.

🔍 Diagnosing and Treating Puberty Delays

Diagnosing a delayed puberty typically involves evaluating the individual's progression through the Tanner stages and measuring hormone levels. A family history of constitutional delay can indicate a genetic component. Treatment depends on the cause: constitutional delays may resolve naturally, while underlying medical conditions like hypogonadism require hormone therapy to initiate puberty. In some cases, fertility treatments may be needed if puberty is severely delayed or does not progress normally.

Keywords

💡Puberty

Puberty is the period during which an individual's body undergoes significant changes to become sexually mature. It is a critical phase for the development of primary and secondary sexual characteristics. In the script, puberty is discussed as a time when the body's hormonal signaling system activates to initiate these changes, typically starting around age 13 for females and 14 for males.

💡Hypothalamic Pituitary Gonadal Axis

The Hypothalamic Pituitary Gonadal (HPG) Axis is a hormonal signaling system that controls sexual development and reproduction. It involves the hypothalamus, pituitary gland, and gonads (testes or ovaries). The script explains how this axis is activated during puberty, with the hypothalamus releasing hormones that stimulate the pituitary gland to produce gonadotropins, which in turn stimulate the gonads to produce sex hormones.

💡Gonadotropin Releasing Hormone (GnRH)

Gonadotropin Releasing Hormone is a hormone produced by the hypothalamus that plays a crucial role in puberty by stimulating the pituitary gland to release other hormones. The script mentions GnRH as the trigger for the HPG axis, initiating the production of luteinizing hormone and follicle-stimulating hormone.

💡Luteinizing Hormone (LH) and Follicle Stimulating Hormone (FSH)

Luteinizing Hormone and Follicle Stimulating Hormone are gonadotropins that stimulate the gonads to produce sex hormones. In the script, LH and FSH are described as being released by the pituitary gland in response to GnRH, which then act on the testes or ovaries to produce testosterone, estrogen, and progesterone.

💡Sex-specific Hormones

Sex-specific hormones are those that are unique to one sex and play a role in the development of sexual characteristics. The script identifies testosterone as the major sex-specific hormone in males, while estrogen and progesterone are the primary ones in females. These hormones are responsible for the development of secondary sexual characteristics during puberty.

💡Primary and Secondary Sexual Characteristics

Primary sexual characteristics refer to the genitals and their direct involvement in sexual reproduction, while secondary sexual characteristics are physical traits not directly involved in reproduction, such as body hair and breast development. The script explains how sex hormones drive the development of these characteristics during puberty.

💡Tanner Scale

The Tanner Scale is a set of stages that describe the development of primary and secondary sexual characteristics during puberty. The script uses the Tanner Scale to illustrate the progression of puberty in males and females, detailing the changes in pubic hair, testes, penis, and breast development.

💡Hypogonadism

Hypogonadism is a condition characterized by low levels of sex hormones due to low gonad activity. The script discusses hypogonadism as a central cause of delayed puberty, leading to underdeveloped sex characteristics and potential infertility if puberty never begins or completes.

💡Primary Hypogonadism

Primary Hypogonadism is a type of hypogonadism caused by dysfunction of the gonads themselves. The script mentions that this can result from the gonads' receptors not responding to gonadotropin hormones or from a lack of healthy cells capable of hormone production.

💡Secondary Hypogonadism

Secondary Hypogonadism is a type of hypogonadism caused by dysfunction in the hypothalamus or pituitary gland, leading to low levels of gonadotropin-releasing hormones. The script explains how this can be due to an inability to produce these hormones or suppression from other hormones.

💡Constitutional Delay

Constitutional Delay is a temporary delay in puberty that is not pathological but rather a naturally slowed rate of maturation. The script notes that puberty can still occur naturally in these cases, but at a later age, often with a genetic component.

Highlights

Puberty marks the time when individuals physically become sexually mature and able to have children.

Delayed puberty is typically diagnosed if puberty hasn't started by age 13 in females and 14 in males.

The hypothalamic-pituitary-gonadal axis is crucial in regulating sexual development and reproduction.

Gonadotropin-releasing hormone (GnRH) stimulates the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from the pituitary gland.

LH and FSH then trigger the gonads (testes in males, ovaries in females) to produce sex-specific hormones like estrogen and testosterone.

In males, testosterone helps develop external sex organs and begins sperm production during puberty.

In females, estrogen and progesterone drive ovarian and menstrual cycles, supporting egg maturation and ovulation.

Primary sex characteristics refer to the genitals, while secondary sex characteristics include features like pubic hair and breast development.

The Tanner scale outlines five stages of puberty, measuring changes like pubic hair growth, breast development, and genital enlargement.

Hypogonadism results in delayed puberty and can be either primary (gonadal dysfunction) or secondary (pituitary or hypothalamic dysfunction).

Primary hypogonadism leads to low sex hormone levels but increased LH and FSH levels, termed hypergonadotropic hypogonadism.

Secondary hypogonadism, or hypogonadotropic hypogonadism, involves low LH and FSH levels due to issues in the hypothalamus or pituitary.

A third cause, constitutional delay, is a naturally slow maturation that usually resolves without medical intervention.

Blood tests and Tanner scale comparisons help diagnose the type of hypogonadism causing the delay in puberty.

Hormone therapy is often used to treat underlying medical conditions causing delayed puberty and may help ensure fertility.

Transcripts

puberty is the time in an individual's

life when they physically become

sexually mature and able to have

children generally speaking it's

considered delayed if puberty hasn't

started for a female by the age 13 and

for a male by age 14.

the hypothalamic pituitary gonadal

access is a system of hormonal signaling

between the hypothalamus pituitary gland

and gonads the gonads are either the

testes or the ovaries and this will

control sexual development and

reproduction

the natatropin releasing hormone is

released into the hypotheseal portal

system which is a network of capillaries

connecting the hypothalamus to the

hypothesis or pituitary

when gonadotropin releasing hormone

reach the pituitary gland it stimulates

cells in the interior pituitary called

gonadotrophs to release genetotrophin

hormones luteinizing hormone and

follicle stimulating hormone which then

enter the blood these gonadotrophin

hormones then stimulate the gonads to

produce sex-specific hormones these are

estrogen and progesterone in females and

testosterone is the major sex-specific

hormone in males

early on in male development

testosterone helps the external sex

organs to differentiate into male

genitals and causes the testes to

descend from the abdomen into the

scrotal sac

beginning at puberty the leydig cells of

the testes respond to the luteinizing

hormone by converting more cholesterol

into testosterone

in addition the sertoli cells of the

testes respond to follicle stimulating

hormone by producing more sperm

the major sex specific hormones in women

are estrogen and progesterone and they

are produced by the ovarian follicles

that are scattered on the ovaries

each ovarian follicle is made up of a

ring of granulosa and fecal cells

surrounding a primary oocyte at its core

beginning at puberty fecal cells respond

to luteinizing hormone by producing

androstenedione and androgen

then the granulosa cells respond to

follicle stimulating hormone by

converting the androstenedione into

estrogen and progesterone

waves of estrogen and progesterone

regulate monthly changes to the ovary

stoma to promote egg maturation and

ovulation and as well it changes to the

uterine wall lining as part of the

menstrual cycle

the increased production of sex hormones

drives the development of primary and

secondary sex characteristics that we

see during puberty primary sex

characteristics refer to the genitals

which are the organs directly involved

in sexual reproduction secondary sex

characteristics refers to any

sex-specific physical characteristic

that is not directly involved or

necessary in sexual reproduction like

pubic hair in breasts and females

the tanner scale or tanner stages is a

predictable set of steps that males and

females go through as they develop

primary and secondary sex

characteristics and become sexually

mature the tanner scale centers on two

independent criteria the appearance of

pubic hair in both sexes and the

increase in testicular volume and penile

size and length in males and breast

development in females

there are five stages in stage one the

pre-pubertal stage no pubic hair is

present in either sex males have a small

penis in testes females have a flat

chest

in stage 2 pubic hair appears and

there's a measurable enlargement of the

testes and breast buds appear

in stage three pubic hair becomes

coarser the penis begins to enlarge in

both size and length and breast mounds

form

in stage four pubic hair begins to cover

the pubic area the penis begins to widen

and breast enlargement continues to form

something called mound on mound contour

in stage five pubic hair extends to the

inner thigh the penis and testes have

enlarged to adult size and the breast

takes on an adult contour

puberty is delayed if progression

through the tanner scale hasn't begun by

the time 95 percent of an individual's

peers have begun to sexually mature

generally that means puberty has not

started by age 13 in females and age 14

in males

hypogonadism or lower levels of sex

hormones from low gonad activity is

central to a delay in puberty as a

result sex characteristics are

underdeveloped

permanent infertility can occur if

puberty never begins or fails to

complete and sexual maturity is never

reached

there are two main causes of

hypogonadism

the first is primary hypogonadism which

is caused by dysfunction of the gonads

for example the gonads receptors may not

respond to gonadotropin hormones

or the gonads might not have healthy

cells that are capable of producing

hormone

some acquired cases of primary

hypogonadism are radiation therapy

chemotherapy and trauma to the gonads

some congenital causes of primary

hypogonadism are genetic diseases like

kleinfelder or turner syndrome

regardless of the cause the result is a

decrease or absence of testosterone in

males or estrogen and progesterone in

females

which means there's no negative feedback

on the hypothalamus this leads to an

overproduction of luteinizing and

follicle stimulating hormones so primary

hypogonadism is also called

hypergonadotropic hypogonadism

the second cause of hypogonadism is

secondary hypogonadism which is also

called hypogonadotropic

hypogonadism because there are low

levels of luteinizing and follicle

stimulating hormones

secondary hypogonadism can be due to

hypothalamus or pituitary gland

dysfunction either from an inability to

produce gonadotropin releasing hormone

or luteinizing and follicle stimulating

hormones

or suppression from other hormones like

prolactin or thyroid hormone

some acquired cases are similar to

primary hypogonadism radiation therapy

chemotherapy and trauma to the gonads

other ones include a tumor of the

pituitary gland and hypothalamus and

congenital causes include common

syndrome and

pan-hypopituitarism and general causes

include chronic illness like cystic

fibrosis or celiac disease

excessive exercise

malnutrition or obesity and stress all

of which affect the way the hypothalamus

and pituitary release hormones

a third category called constitutional

delay is a temporary delay in puberty

which does not typically result in

infertility

just like in secondary hypogonadism

there is a lack of gonadotrophin

releasing hormone but the key difference

is that it's not considered pathologic

instead it's thought to be a naturally

slowed rate of maturation the onset of

puberty can still occur naturally and

puberty can progress normally after

onset it just all happens at a later age

typically there's a genetic component to

constitutional delays and it runs in

families

a delay in puberty is usually diagnosed

by comparing an individual's sexual

development with the tanner scale

blood tests of hormone levels can give

an idea of the type of hypogonadism

and a detailed medical history including

evaluating any underlying medical

conditions and family history for

constitutional delay can be helpful

the treatment for a delay in puberty

depends on the cause a constitutional

delay can resolve on its own with a

natural onset of puberty and does not

typically require medical intervention

if an underlying medical condition is

the cause hormone therapy is necessary

to ensure the onset and normal

progression of puberty

infertility treatments may also be

needed to make reproduction possible

to recap delayed puberty usually means

that it hasn't started for a female by

age 13 and for a male by age 14.

though there are different causes which

result in different levels of

gonadotrophin hormones they all

ultimately result in hypogonadism and a

deficiency in testosterone or estrogen

and progesterone

in contrast a constitutional delay is

when the onset of puberty might still

occur naturally with puberty progressing

normally after onset but it just occurs

at a later age

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