Puberty Flashcards
What is adrenarche, and when does this occur?
-Regeneration of the zona reticularis in the adrenal cortex
Occurs between ages 6-8
What is gonadarche, and when does this begin?
Pulsatile release of GnRH from the hypothalamus begins, causing release of LH/FSH
Are there phenotypic changes with adrenarche? Gonadarche?
No
What are the basophils of the anterior pituitary? Acidophils?
B-FLAT
GPA
What is thelarche, and what does it occur? What occurs with this?
Occurs around age 11
Breast bud development and first phenotypic signs of puberty
During what stage of puberty do phenotypic changes occur? What is the hormone that is responsible for this?
Thelarche
Estrogen
What is pubarche, and when does this occur? What causes this to occur?
Onset of pubic and axillary hair growth around age 12
result of increased androgens
True or false: having pubarche prior to thelarche is a concerning finding
False- normal variant, especially in black females
Pubarche precedes menarche by approximately how many years?
2
What is menarche, and what does this occur?
Onset of menses
Avg age 12.5 years
How long does it take for menstrual cycles to become regular?
2 years
What is the very first sign of puberty?
Growth acceleration
What hormone is responsible for increasing estrogen production?
FSH
What hormone is responsible for increasing androgens and progesterones production?
LH
What is the main form of estrogen?
Estradiol
What is the enzyme that converts testosterone to estrogen?
Aromatase
What is the general progression of the HPA axis from in utero to childhood?
High in utero, but drops after delivery d/t loss of maternal hormones.
Pulsatile release increases in infancy, peaking around 12-18 months, when negative feedback ensues
What happens to the HPA axis in the prepubertal years?
Downregulation of HPA with reduction in GnRH
-Increases in ovarian size and vaginal length
What happens to the uterine body / cervix ratio as females progress through childhood?
Increases (1:1 to 3:1)
What happens to GnRH production around 8 years of age?
Increased amplitude and frequency of GnRH release
Which is produced in larger amounts during puberty: LH or FSH?
LH
What is the positive and negative feedback mechanisms on the HPA axis with estrogen?
Estrogen increases LH/FSH alone, but decreases with inhibin
When does the growth peak occur?
2 years after breast budding and 1 year prior to menarche
True or false: there is limited growth potential after menarche. Why or why not?
True since epiphyseal plates close
What fraction of total body calcium is laid down during puberty
1/2
How long is the process of sexual maturation for girls?
4.5 years
What is the definition of precocious puberty (breast, pubic hair, and menstruation times)?
- Breast development before 7 years
- Pubic hair development before 8 yr
- Menstruation before 10 yr
In which gender does precocious puberty happen more often?
Girl:boy 23:1
What are the two general types of precocious puberty?
GnRH dependent or independent