Female Reproductive System Flashcards
What are the functions of the ovaries?
Storage and release of the ovum and production and estrogen and progesterone
From what structure are the uterus, fallopian tubes, and vagina derived?
Mullerian ducts
To what cells does LH bind in females?
Theca cells of the ovary;
To what cells does FSH bind in females?
Granulosa cells of the ovary;
What is the function of specifically FSH in females? Specifically LH? Both LH and FSH?
FSH- follicular recruitment and development; LH-Ovulation; FSH and LH- estrogen and progesterone release
What are the two phases of the ovarian cycle? What occurs during each and which hormones stimulate them?
Follicular phase- follicular recruitment and growth and estrogen synthesis- mostly FSH stimulation; and luteal phase- progesterone and estrogen synthesis from the corpus luteum- mostly LH stimulation
What phase if the endometrium in when estrogen is the predominant hormone in the blood?
Proliferative phase
What are the endometrial phases?
Proliferative phase–> secretory phase–> menstruation–>
In what stage are oogonia at birth?
Primary oocytes
What is ovulation?
Rupture of the follicular surface and release of oocyte and corona radiata
At what point in the female reproductive cycle is LH present in highest concentrations? What stimulates this high release?
12-24 hours pre-ovulation; Feed forward stimulation by estrogen
What structure develops from the ruptured follicle following ovulation? What is its function?
Corpus luteum; Produces progeterone and estradiol to maintain early gestation
What is necessary for survival of the corpus luteum?
Fertilization and the initial steps in placental formation resulting in hCG release
What occurs during the proliferative phase of the uterus? What is the primary hormone that regulates it?
Proliferation, increase expression of estradiol and progesterone receptor; Estrogen
What occurs during the secretory phase of the uterus? What is the primary hormone that regulates it?
Differentiation of epithelial cells to secretory cells; Progesterone
How is estrogen produced within the ovary?
Theca cells convert cholesterol to androdstenedione and Granulosa cells convert the androgens to estradiol
True or False: The synthesis of androgen parallels estrogen throughout the menstrual cycle
True
What circulating hormone gives an indication of corpus luteum function?
Inhibin A
What circulating hormone is an index of granulosa cell function
Inhibin B
What is the effect of activin?
Increased granulosa cell proliferation, increased FSHr expression, increased steroidogenesis, and stimulates FSH and LH release
True or False: the conversion of androgens to estrogens is freely reversible
False- irreversible
What causes the difference in sex hormone levels in males vs females?
How much androgen is made and what percentage of it is converted to estrogen (females have more aromatase expression)
How can estrogen and progesterone be metabolized?
Estrogen can undergo conversion to estrone, estriol, and 2-methoxyestrone; Progesterone can be converted to pregnenolone and then pregnandiol
To what receptors does estrogen bind? Progesterone? In what tissues are they expressed? What etrogen type is predominant in reproductive tissues?
Estrogen alpha and beta receptors and progesterone A and B expressed in uterus, ovary, breast, bone, brain, cardiovascular– mostly alpha in reproductive tissues
How does estrogen affect progesterone receptors?
Upregulates their expression
True or False: Estrogen can mediate non-genomic effects.
True
How does estrogen affect the uterus?
Stimulates proliferation of the endometrium and sensitizes it to oxytocin by increasing oxytocin receptors and contractile proteins, increases cervical mucus production
How does estrogen affect the ovary?
Mitotic effects on granulosa cells and increases the FSH-mediated differentiation process
How does estrogen affect the breast?
Increased ductal epithial growth and differentiation, and increased mammary progesterone receptor expression
What are the non-reproductive effects of estrogen? (Liver, brain, bone)
Increases lipoproteion receptor expression, increases HDL and decreases total cholesterol and LDL, decreases fibrinogen antithrombin III and PAI-1, increases thyroid and cortisol binding globulin; neuroprotection; increased bone maturation, epihpyseal plate closure, decreased bone turnover and decreased osteoclast activity
What are the effects of progesterone on the ovary?
Decreased follicular atresia, promotes oocyte maturation
What are the effects of progesterone on the uterus? During pregnancy?
Increases growth, differentiation and glandular secretions; during pregnancy it decreases contractility, decreases alpha adrenergic receptor expression, decreases prostaglandin synthesis, and increases relaxin and distensibility
How does progesterone affect breast tissue?
Prepares the breast for lactation by increasing lobular-alveolar development, decreased prolactin effects
How does progesterone affect the brain?
Modulates sexual behavior and increases body temperature
What is the function of anti-mullerian hormone in females?
Inhibition of primordial follicle recruitment- maintain the right tempo of folliculogenesis
What hormone can be used as a biomarker of ovarian reserve?
anti-Mullerian hormone
What changes occur during capacitation?
Changes in the sperm plasma membrane, increased affinity of the sperm for the zona pellucida, synthesis of enzymes for the acrosome reaction
What is the problem with low birthweight?
Associated with an increased risk for mortality, neurologic dysfunction, and adult onset disease
What are the functions of the placenta?
Support (embryo implantation and nutrients for fetal growth), prevent maternal immunologic rejection of fetus, endocrine function to promote fetal growth and survival
True or False: human chorionic gonadotropin can only be found in fetal circulation
False
What tissue produces human chorionic gonadotropin? When does its production peak?
Placenta; Peaks at end of 1st trimester
What is the effect of human chorionic gonadotropin?
Prevents regression of corpus luteum, stimulates CL hormone synthesis
At what point can human placental lactogen be found in maternal and fetal circulation?
6 weeks
What is the effect/function of placental lactogen?
Increases IGF production, regulates insulin, adrenocortical hormone, and pulmonary surfactant production
What is the role of human growth hormone-V?
Plays a role in intermediary metabolism, increases fetal glucose and amino acids, replaces maternal pituitary GH, ensures adequate supply of nutrients from mother to fetus
What is the role of placental progesterone?
Uterine quiescence, decreases prostaglandin synthesis, and immunomodulation
What is the role of placental estrogen?
Increased uterine growth, prostaglandin synthesis, thickening of vaginal wall, sensitization to oxytocin, growth and development of mammary epithelium, inhibition of milk production
True or False: During pregnancy the placenta increasingly secretes CRH?
True
How does the fetoplacental unit work together to synthesize and metabolize sex steroids?
The mother’s liver converts acetate to cholesterol which is transferred to the placenta where it is converted to pregnenolone. Pregnenolone can be converted to progesterone or be transported to the fetal adrenal cortex to be converted into DHEA which can reenter the placenta to be converted to estriol which can be conjugated in the maternal liver and excreted by the kidney
What is secreting estrogen and progesterone in the third trimester?
Just the placenta
What are the phases of uterine activity in parturition?
0- Quiescent; 1- Activation, 2- Active uterine contraction, 3- postpartum uterine involution
What are the steps of breast development, what are the hormones involved in each step, and when does each process occur?
Ductal elongation (Puberty; Estrogen, GH, IGF-1, EGF), Ductal branching and budding (Sexual maturation and pregnancy; Progesterone, estrogen, cortisol, prolactin, T3/T4), and Expansion and differntiation (Pregnancy and Post-partum lactation; Prolactin, IGF-1, hPL, cortisol, insulin, oxytocin
What is the first change associated with puberty in females?
Increased nocturnal LH and FSH pulses
What changes occur with female puberty?
Skeletal maturation (epiphyseal fusion and increased bone mass), breast development, ovarian and follicular growth, pubic and axillary hair, onset of menses
What is required for the initial pulsitility of estrogen and GH in female puberty?
Adipose-derived leptin
What are the initial stages of menopause characterized by? What causes this?
Increased release of GnRH due to the decreased ability of ovary to make hormones, decreasing negative feedback inhibition from inhibin and estrogen
What happens to the ratio of androgens/ estrogens in menopause?
Increases because the adrenals have not lost the ability to make androgens but ovaries have lost ability too make estrogens
What are the risk factors for developing osteoporosis?
Decreased sex hormones, chronically elevated glucocorticoids and thyroid hormone, prolonged immobilization, GI disorders, malignancy, alcoholism, cigarette smoking
What does DEXA measure?
Bone density
What is FRAX?
A fracture risk prediction tool proposed by the WHO that incoporates DEXA and clinical risk factors
