Delayed puberty - causes, symptoms, diagnosis, treatment, pathology
Summary
TLDRPuberty 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
🌱 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.
🧬 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.
Mindmap
Keywords
💡Puberty
💡Hypothalamic Pituitary Gonadal Axis
💡Gonadotropin Releasing Hormone (GnRH)
💡Luteinizing Hormone (LH) and Follicle Stimulating Hormone (FSH)
💡Sex-specific Hormones
💡Primary and Secondary Sexual Characteristics
💡Tanner Scale
💡Hypogonadism
💡Primary Hypogonadism
💡Secondary Hypogonadism
💡Constitutional Delay
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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