Reproduction 2 Flashcards
primary amenorrhea
absence of menses in phenotypic female by age 17
- e.g. Turner syndrome (XO), androgen resistance
secondary amenorrhea
cessation of menstruation for longer than 6 months
- e.g. pregnancy, lactation, menopause
oligomenorrhea
infrequent periods (cycle length >35 days) - e.g. stress, illness, changes in body fat, intense exercise
dysmenorrhea (& what promotes prostaglandins)
painful menses related to uterine contraction, nausea, vomiting, diarrhea
- E2 and progesterone promote prostaglandins which cause uterine contractions
causes and consequences of PCOS
insulin resistance and obesity
how does high insulin impact ovaries? what do you treat with?
stimulates androgen production, causing impaired follicle development and no ovulation; follicles degrade into cysts and ovaries double in size
- treat with metformin
when is the window of opportunity for fertilization?
24 hours post-ovulation for the ovum and 48-72 hours post-coitus for the sperm
where does fertilization occur?
in the fallopian tubes
two exocytotic events during the fertilization process
1) Exocytosis of spermatozoan internal membrane contents- allows sperm to attach to zona pellucida
2) Exocytosis of oocyte’s internal vesicles- harden the rest of the zona pellucida (Ca2+ mediated- also triggers second meiotic division after metaphase II)
what primes female tract to aid sperm transport to the oviduct; what facilitates and what enhances sperm motility
- primes: estrogen
- facilitates: decreased acidity and viscosity of mucus
- enhances: ciliary movement, peristaltic movement, fluid flow
cGMP enhances velocity and direction
what three processes is embryo implantation made up of?
adhesion, penetration, invasion
what happens during adhesion?
- zona pellucida dissolves
- Il-1 increases integrins in endometrial cells
- osteopontin (bridging molecules) binds integrins together
- trophopblasts develop
what happens during penetration?
- stromal cells of endometrium enlarge to form the decidua (progesterone-promoted) and secrete nutrients (source until placenta)
- cells preform some endocrine functions (e.g. prolactin)
what happens during invasion?
- find balance between decidual cells and trophoblast migration
- trophoblasts differentiate into syncytiotrophoblasts (like pituitary- most endocrine functions, makes hCG/hCL) and cytotrophoblasts (like hypothalamus- CRH, TRH, somatostatins)
functions of the placenta
1) gut- supplies nutrients
2) lungs- gas exchange (high pCO2)
3) kidneys- regulating fluid volume and waste disposal (urea, creatinine)
4) endocrine gland
what is hCG produced by/what is it under the control of?
produced by syncytiotrophoblasts, under control of GnRH from cytotrophoblasts
what does high hCG signal?
- negative feedback on maternal pituitary to prevent LH/FSH secretion (which would normally stimulate next cohort of follicles to develop)
- rescues corpus luteum, stimulates progesterone and estradiol
what is hPL?
HCS aka human placental lactogen (HPL)
- similar to growth hormone
- stimulates lipolysis and has anti-insulin effects on maternal metabolism
- leads to increase in plasma glucose and FFA for fetus
- cause of gestational diabetes
T/F Gestational age is two weeks less than fetal age
FALSE- “Fetal age” is about 2 weeks less than gestational age.
T/F 100 or less sperm arrive at distal end of the fallopian tube
FALSE- 50 or less
what is relaxin produced by and what does it do?
- produced by: corpus luteum and placenta
1) inhibits myometrial (uterine) contractions
2) relaxes pelvic bones
3) softens cervix
T/F Prolactin comes from the placenta
FALSE- from maternal pituitary
what is lactation inhibited by?
estrogen and progesterone
what is the major estrogen of pregnancy
- estriol
how is estriol produced?
mom’s cholesterol (LDL)- pregnenolone in placenta- converted by fetal adrenal to DHEA-S- converted by fetal liver to oh-DHEA-S- sulfer removed by placenta- placenta makes estriol
what does the conjugation of sulfur do?
makes it more water soluble, less bioactive
effects of progesterone during pregnancy
establishment/sustenance of the fetus including:
- inhibiting uterine contractions/prostaglandins
- decreasing sensitivity to OXT
- inhibits maternal immune response
- mammogenesis- alveolar pouches, capacity to secrete milk
effects of estrogens during pregnancy
- mammogenesis- growth of ducts
* growth of myometrium, softens pelvis, enlargement of genitalia
describe the estrogen:progesterone ratio
estrogen progesterone- birth
what are the actions of progesterone and estrogen in birth control?
progesterone- prevents LH secretion
estrogen- inhibits FSH
cardiovascular changes in pregnancy
increased CO- HR and SV reversible cardiomegaly 50% increase in blood volume MAP decreases TPR decreases venous pressure increases uterus gets 30% of CO skin blood flow increases (increased metabolism) blood flow to kidneys increases
respiratory changes during pregnancy
increase in tidal volume
no change in frequency
GI changes with pregnancy
decreased motility, greater nutrition assimilation
LES tone decreased
metabolic changes with pregnancy
first 1/2- mom in anabolic state, increases fat and glycogen stores
second 1/2- catabolic state with insulin resistance mediated by HPL
cortisol’s relationship to parturition
- CRH peaks at labor (no surge though)
- potentiates contracture response to PGEs/OXT
- CRH from placenta/fetus increases E2
how does myometrial cell contracture change with parturition?
- decrease in P:E2 ratio
- increases local prostaglandins
- increased cell Ca++
- more forceful contractions
T/F Maternal oxytocin initiates labor
FALSE- released in bursts once labor beings, has positive feedback loop, stimulating prostaglandin release
- stimulus is distention of the cervix: Ferguson reflex
catecholamine actions during parturition
alpha-adrenergics- stimulates contraction
beta-adrenergics- inhibits contraction
E2& prostaglandins increase alphas
stress can precipitate labor
how does lactating reduce fertility?
neural inputs from spinal cord have inhibitory action on arcuate nucleus and pre-optic nuclei causing a decrease in GnRH
