Female Puberty Flashcards
What is adrenarche?
The production of sex hormones from the adrenal gland
When does adrenarche begin in girls?
6-8 yo. This occurs before any perceived phenotypic changes occur and is associated with regneration of androgen production from the zona reticularis
What are the main phases of female puberty in order?
- adrenarche
- gonadarche (the increase in estrogens leads to the following stages)
1) growth acceleration
2) Thelarche, or development of breasts (stimulated by estradiol form the ovaries)
3) Pubarche, or the development of pubic hair (stimulates vy androgens from the adrenal gland)
4) Maximum growth rate
5) Menarche
T or F. Mild to moderate obesity leads to earlier puberty
T.
Notes about Gonadarche: this occurs when increased pulsatile GnRH secretion leads to subsequent release of LH and FSH and begins around age 8 in girls. Intitially these increases occur mostly during sleep and fail to lead to any phenotypic changes, but eventually LH and FSH pulsatility lasts throughout the day leading to stimulation of the ovary to begin estrogen production
T or F. During puberty there is up to 2x higher rates of depression in girls than in boys
T. Girls tend to struggle with the changes more. This trend has been found to be more pronounced in white girls
What is precocious puberty?
The onset of secondary sexual development prior to the age of 7 in white girls and 6 in AA girls
The timing of puberty is variable but 99% have the frist signs of sexual development between 8-13.
What are some GnRH-dependent causes of precocious puberty?
- Most commonly idiopathic (80-90%)
- Infection/Inflammation of CNS
- Rarely a tumor of the hypothalamic- pituitary stalk (hamartomas, astrocyotmas, ependymomas, pineal tumors, etc.)
- Primary hypothyroidism (TSH directly activates the FSH receptor)
What are some GnRH-independent causes of precocious puberty?
McCune Albright Syndrome (independent production of estrogen from the ovaries without FSH stimulation, bone fractures, and cafe au lait spots
- Adrenal tumors or CAH
- Iatrogenic estrogen administration
- ovarian cysts (most common cause: follicular cysts of the ovaries)- pts. often present with episodes of vaginal bleeding
- ovarian tumors
A rapid-progression of precocious puberty suggests what as a potential cause?
GnRH-indepenedent cause such as a tumor
Evaulation of precocious puberty
1) Hx with pubertal staging
2) Radiographic evaluation of bone age
3) baseline LH level (high suggest GnRH dependent)- then go to brain imaging
4) GnRH agonist
What is delayed puberty defined as?
The lack of development of secondary sex characteristics by age 13
no evidence of menarche by age 15-16
no menses within 5 yrs of thelarch
How would hypergonadatropic hypogonadism cause of delayed puberty present in labs?
elevated FSH and LH
Hypergonadotropic hypogonadism (HH), also known as primary or peripheral/gonadal hypogonadism, is a condition which is characterized by hypogonadism due to an impaired response of the gonads to FSH and LH and in turn a lack of sex steroid production and elevated gonadotropin levels (as an attempt of compensation by the body)
What is the most common cause of hypergonadatropic hypogonadism?
Turner Syndrome (XO), the lack of an X chromosome that present with short statue, webbed neck, solid chest, and streak ovaries
How is Turner syndrome treated?
estrogen administration which will stimuate breast development and genital tract maturation
What is the most common cause of a hypogonadotropic hypogonadism (lack of GnRH secretion) cause of delayed puberty?
constitiutional delay- tends to be familial
Kallman Syndrome
cranippharyngioma
anorexia, exercise, stress
Causes of primary amenorrhea in girls with normal breast development
1) Mullerian agenesis (Mayer-Rokitansky Kuster Hauser Syndrome)- congenital absense of the vagina and/or uterus and fallopian tubes. Pt. will have normal ovaries
2) Imperforate hyman- obstruction of menstrual blood. Pt will have uterine pain
Describe adrenarche
Adrenarche is one of the first manifestations of puberty, occurring at age 6-8, and characterized by the production of increased quantities of adrogenic steroid hormones such as DHEAS, DHEA, and Androstenedione from the adrenal cortex.
Production of these hormones increases from age 6-8 till age 13-15
What is Gonadarche?
In response to increased pulsatile secretion of GnRH from the hypothalamus, the ovaries in girls and the testes in boys begin to grow and increase the production of the sex steroids, especially estradiol and testosterone in response to LH and FSH.
Initially, these increases occur mostly during sleep and fail to lead to any phenotypic changes, but eventually LH and FSH pulsatility lasts throughout the day leading to stimulation of the ovaries to produce estrogens
When does gonadarche typically begin?
Age 8