TBL Pregnancy and Lactation Flashcards
(124 cards)
1
Q
What does estrogen (high amounts or low amounts) do for the females?
A
causes proliferation of endometrium thinning of cervical mucus stimulate pituitary to secrete LH LH surge at mid-cycle-> ovulation stimulate progesterone production
2
Q
LH surge causes completion of (blank)
A
meiosis I in the preovulatory follicle
3
Q
What stage is the oocyte in 3 hrs before ovulation?
A
arrested in metaphase of meiosis II
4
Q
What is happening on the ovarian surface during ovulation?
A
You have increase LH which will increase collagenase which will digest fibers to allow for ovulation.
Increase LH will increase prostaglandin which will increase muscular contraction
5
Q
What are the lutean cells?
A
granulosa cells and theca cells
6
Q
What does the corpus luteum secrete?
A
progesterone and estrogene
7
Q
What does progesterone and estrogen do to the uterus?
A
turns the uterine mucosa into progestational/secretory stage in preparation for implantation
8
Q
How do we get the ovulated oocyte into the uterus?
A
via fimbriae of uterine tube and cilia on eptihelium
9
Q
How long does it take for the oocyte to transport from ampulla to uterine lumen?
A
3-4 days
10
Q
Where does fertilization occur?
A
at the ampulla of the uterine tube
11
Q
What happens if there isnt fertilization?
A
lutean cells undergo apoptosis and you get a corpus albicans and decrease of progesterone which will result in menstrual bleeding
12
Q
If the oocyte is fertilized what will happen?
A
hCG secreted by syncytiotrophoblast further growth
13
Q
How long will the corpus luteum secrete progesterone?
A
for four months until the trophoblast takes over the secretion of progesterone
14
Q
Explain the transport of spermatozoa in the male
A
epidydimis (via testicular fluid)-> maturation in epididymis-> ductus deferens-> seminal vesicles-> prostate
15
Q
Explain the transport of spermatozoa in the female
A
upper vagina (rapid elevation of pH)-> cervix-> uterus-> uterine tubes
16
Q
How many sperm enter the vagina and then on?
A
vagina (10^7)-> cervix (10^6)->uterus (10^5)-> uterine tubes (10^4)-> near egg (10^2-3)
17
Q
How many sperm arrive at distal end of fallopian tube?
A
50 or less
18
Q
What day is the egg at the ampullary-isthmic junction after ovulation (where fertilization occurs)?
A
days 1-2
19
Q
What day is the egg at the utero-tubal junction after ovulation?
A
days 2-3
20
Q
How many days does the egg take to enter the uterine cavity as a morula?
A
days 3-4
21
Q
How many days after ovulation does the blastocyst implant?
A
day 7
22
Q
What is capacitation?
A
maturation of sperm in female reproductive tract.
removal of glycoproteins and seminal plasma proteins form sperm PM
23
Q
What is the acrosome reaction?
A
release of enzyme by sperm to dissolve ZP
24
Q
Where does fertilization occur?
A
at ampulla of uterine tube
25
What is phase I of fertilization?
penetration of corona radiata
26
What is phase II of fertilization?
Penetration of zona pellucida
27
What is phase III of fertilization?
fusion of the oocyte and sperm cell membranes
28
How long does it take for the sperm to penetrate the zona pellucida?
15-25 min
29
How long does the sperm spend in the perivitelline space?
less than 1 seconda
30
How long is the sperm in the perivitelline membrane?
less than 1 minute
31
How long does it take for male and female pronuclei to be visible and when does the first mitotic cleavage occur?
2-3 hours
| 24 hours
32
What does the entry of a sperm into the oocyte trigger?
cortical and zona reactions to prevent polyspermy
Oocyte completes meiosis II
egg is activated
33
When the sperm enters the egg what happens to the membrane?
it depolarizes plasma membrane of egg (allows for calcium mobilization) which will trigger proteases to take out carbs from ZP3 and change them to ZP2 to prevent polyspermy
34
What are the results of fertilization?
restoration of diploid number of chromosomes
sex determination
initiation of cleavage
35
What is a blastomere?
a cell formed by cleavage of a fertilized ovum
| 2,4,8 cell stages, makes blastomere smaller and smaller
36
What is compaction?
segregation of inner and outer cells
37
When does a blastomere become a morula?
when the blastomere becomes a 16 celled item on day 3
38
What is the inner cell mass of the morula?
| What is the outer cell mass of the morula?
embryo proper-> tissues
| trophoblast-> placenta
39
Explain a blastocyst
ZP degenerates-> uterine fluid penetration-> blastocele (cavity) formation, the inner cell mast become the embryoblast, the outter cell mass becomes the trophoblast, epithelial wall
40
When does the ovum implant?
during the secretory phase
41
What are the 3 layers of the endometrium during implantation?
compact layer, spongy layer, and basal layer
42
Where does implantation occur?
along the anterior or posterior wall
43
What are the effects of the progesterone on the uterine endometrium?
highly secretory
| makes nutrients and deciduous environment
44
What happens after progesterone makes the decidual environment of the endometrium?
trophoblast invade decidua and release nutrients to allow for embryonic development and growth
45
What is the main source of nutrition week 1-8?
trophoblasts :)
46
After week 8 of embryonic development what starts to give nutrition to the embryo?
placenta gradually takes over
47
Explain the composition of the primary villus?
cytotrophoblastic core with a syncytial layer
48
Explain the composition of the seconary villus?
outside layer of synctiotrophoblast, within this layer is the cytotrophoblast with a mesodermal cell core.
49
Explain the composition of the tertiary villus?
outside layer of synctiotrophoblast, within this layer is the cytotrophoblast with a mesodermal cell core that is converted to blood cells and blood vessels
50
At the end of the 3rd week what will happen?
maternal blood vessels penetrate cytotrophoblast layer to enter intervillous space which surrounds the villi.
51
What do we find within the villi of the cytotrophoblasts? What are these in contact with?
capillaries
| in contact with vessels in chorionic plate and connecting stalk which are connected to intraembryonic vessels
52
At the end of the 3rd week what happens to the tertiary and secondary villi?
the tertiary and secondary villi will give the trophoblast a radial shape.
53
What are the intervillious spaces lined with?
synctium
54
What surrounds the entire trophoblast and is in contact with the endometrium?
Cytotrophoblasts
55
How is the embryo suspended in the chorionic cavity?
by the connecting stalk
56
Explain the placenta
it has maternal vessels (umbilical vein carries oxygenated blood, umbilical artery carries deoxygenated blood). Placental septum, stratum spongiosum, villis, marginal sinus, chorion, amnion, intravillus space, trophoblast
57
What does the placenta do?
it gives O2 and nutrition to the fetus and takes excretory products from fetus to the mother.
58
How does the fetus get oxygen from the placenta?
via the umbilical vein and w/ fetal hemoglobin that has a higher capacity and affinity for oxygen
59
When can hemoglobin bind the most oxygen?
at low Pco2 levels
60
What are some waste products the placenta disposes of?
nonprotein nitrogens-> urea, uric acid, creatinine, CO2
61
What does HcG come from?
from the syncytial trophoblast cells 8-9 days after ovulation
62
When do you have the peak amounts of HcG?
10-12 weeks
63
What does HcG do?
keeps the corpus luteum from degrading
64
You have two progesterone peaks, when are they and what are they from?
1st peak-> recognition of pregnancy, progesterone release from corpus luteum
2nd peak-> placental progesterone secretion (no longer do you need corpus luteum)
65
What is the composition of hCG?
common a + hCG B chain + CHO chain
66
What is hCG B exactly?
it is like LH but with more carbohydrates which makes them have a very long half life (longer than LH)
67
What does hCG target?
it targets corpus luteum and fetal leydig cells to increase testosterone in fetus and stimulate wolffian ducts
68
What singalling mechanism does hCG utilize?
LHR-> cAMP->PKA
69
What is the secretory pattern of hCG?
exponential rise (to maintain corpus luteum,you can use exogenous LH to do this to). And it remains even past the 1st trimester (even after CL involulates)
70
When can you diagnose pregnancy via hCG?
7-10 days after fertilization
71
The synciotrophoblast secretes HCG which will stimulate the ovary (CL) to secrete progesterone and estrogen which will do what to the endometrium? To the anterior pituitary?
progesterone will stimulate the endometrium to become decidual
Estrogen and progesterone will negatively inhibit the release of Gonadotropins from pituitary.
72
What secretes estrogen in the embryo?
synctial trophoblast cells
73
What can you say about the trophoblast?
they provide nutrients for the growing fetus
74
So explain how estrogen is synthesized in the fetus
fetus produces sulfates (in adrenal gland or liver) that can be converted into estrogen by the syncytial trophoblast cells
75
What stimulates the fetal adrenals to create androgens to make estrogen?
CRH and ACTH
76
How does the fetus get estrogen?
From itself-> (estriol E3 (made from liver), and E1 estrone(from cortex))
From mom -> Estradiol (from mamas ovaries) E2 and estrone (E1) from liver
77
Can the placenta convert progesterone to androgens?
nope, this is why you need synctiotrophoblasts
78
What is the significance of the large amounts of estrogen in fetal development?
enlargement of mother's uterus
enlargement of breast and breast ductile structure
enlargement of external genitalia
relaxation of pelvic ligaments
79
Does the fetus make androgens or sulfates to be converted into estrogen?
sulfates :)
80
What does synctial trophoblasts use to make estrogen?
sulfatase (using fetal products)
| aromatases (using maternal products)
81
How do you make estrone from the mom?
materal arenal gland-> DHEA S-> synctotrophoblast-> estrone
82
(blank) is essential for the implantation and the maintenance of pregnanHow cy
progesterone
83
How does progesterone make the female body ready for pregnancy?
```
relaxes uterus (avoid spontaneous abortion)
decidualization of endometrial stroma (nutrition)
increase secretion from fallopian tubes (nutrition to early embryo)
```
84
What does progesterone and estrogen do?
inhibit GnRH pulse generator so you get reduction in LH and FSH
CL stays alive and you get blockade of new way of folliculogenesis
85
Where does human chorionic somatomammotropin/human placental lacogen come from and what does it do?
comes from syncytial trophoblasts and allows for fetal growth, mammary growth, decreased glucose tolerance
86
What is the secretory pattern of human placental lactogen?
increased amounts until 36th week; large amounts
87
What can you use placental lactogen for?
to diagnose decreased placental mass (due to placental infarction)
88
Is placental lactogen dispensible?
NO you need it!
89
What are corticosteroid secretions, relaxin secretions used for?
pregnancy
90
What does the pituitary secrete to allow for pregnancy?
increased corticotropin, thyrotropin, prlactin
| decrease FSH and LH
91
Where does relaxin come from and when does its secretion peak?
produced by corpus luteum, breast,
AND (in pregnancy) placenta chorion and decidua
Peaks during first trimester
92
What does relaxin do?
widens pubic bone and facilitates labor
softens cervix (cervical ripening) and relaxes the uterus
inhibits collagen synthesis and enhances breakdown of collagen by increasing matrix metalloproteinases
enhances angiogenesis
potent renal vasodilator
93
What receptors does relaxin interact with?
LGR7 (RXFP1) and LGR8 (RXFP2) which are G protein receptors
94
Where can we find relaxin receptors?
heart, smooth muscle, CT, and central and ANS
95
What is the mother's response to pregnancy?
```
gains about 24 lbs
increased metabolism (increased 15%)
changes in circulation
```
96
Explain the changes in circulation that the pregnant mother undergoes
```
increased CO by 27th week
Fall in CO in last 8 weeks
Increase Blood volume (due to fluid retention)
Increase respiration
lots of amniotic fluid
```
97
What is preeclampsia?
a condition in pregnancy characterized by high blood pressure, sometimes with fluid retention and proteinuria.
98
What is Eclampsia?
extreme degree of preeclampsia
99
What is this:
Development of hypertension with proteinuria or edema, or both, due to pregnancy or the influence of a recent pregnancy; it usually occurs after the 20th week of gestation, but may develop before this time in the presence of trophoblastic disease.
preeclampsia
100
Explain parturition (birth of the baby)
Increased uterine excitability
increased estrogen and progesterone and oxytocin
increased fetal cortisol, prostaglandins
mechanical stimulation by stretch of uterine wall and cervix
101
What happens at the 7th month of pregnancy?
progesterone levels off and estrogen continutes to increase
102
Where do we get oxytocin in the fetus? cortisol?
fetal pituitary
| adrenal glands
103
What is the onset of labor?
braxton hicks contractions (weak and slow labor contractsion)
104
What triggers the onset of labor?
positive feedback, stretching of cervix by fetus's head, reflex, contraction of uterine body, more stretching, more contraction, more feedback
105
What is this:
babys head stretches cervix
cervical stretch excites fundic contraction
fundic contraction pushes baby down and stretches cervix some more
cycle repeats over and over again
positive feedback of labor
106
Oxytocin admin can induce labor but oxytocin only starts to increase after (blank)
beginning of labor
| hastens delivery, promotes delivery of placenta, reduces bleeding
107
Explain abdominal muscle contraction during labor
uterine contraction-> pain-> neurogenic reflex from spinal cord to abdomen-> contraction
108
Where are contractions the greatest?
at the fundus and decrease down the uterus.
109
Explain the duration of a contraction and describe it
25 lbs of force a contraction and it last 1-3 minutes every 30 minutes.
110
What is the first stage of contractions during labor?
| What is the second stage of contraction during labor?
```
cervix dilation (to size of head of fetus)
Can take up to 8-24 hours
```
membrane rupture, loss of amniotic fluid; head out 1-30 minutes
111
When does the placenta get separated from the wall of the uterus?
10-45 min after birth you get contraction of uterus, prostaglandin release and bleeding
112
There are 2 stages of labor pain, the first stage is done by what kind of innervation?
The second stage?
visceral sensory hypogastric nerves
| somatic nerves to spinal cord and brain
113
How long does it take for the uterus to involute after birth (parturition)?
4-5 weeks
114
What does estrogen do for the breast?
| progesterone?
makes lactiferous ducts, stroma, fat
| makes lobulo-alveolar system
115
What does cortisol, GH, IGF-I, PRL (nonlactating-levels)?
permissive for other hormones to work in the breast
116
What does hCS/hPL and PRL do?
makes alveoli and milk secretion
117
What do estrogene and progesterone do for milk secretion?
inhibit it
118
What does prolactin do for milk secretion?
stimulates it as long as it has cortisol, insulin, Gh and PTH
119
So explain why we dont lactate during pregnancy?
the high levels of estrogen and progesterone inhibit milk secretion so you wont lactate until these levels drop after birth
120
Every time you breast feed what happens?
you get a 10-20 fold increase in PRL for an hour
121
How come women have suppression of ovarian cycle in nursing mothers for many months after delivery?
cuz prolactin inhibits gonadotropin secretion (i.e. you get low LH and FSH) and thus suppresses ovarian cycle
122
How does milk leave the nipple?
it ejects lol, and is triggered to eject by suckling that sends signals to spinal cord and hypothalamus which triggers secretion of oxytocin from posterior pituitary and thus contraction of myoepithelial cells and milk secretion
123
How long does it take for milk ejection to start and to end?
30 seconds to a minute
124
Does the lactation reflex diminish with time?
No,not at all but you do need milk removal to continue lactating
