Module 2 Flashcards
(86 cards)
1
Q
Can your health before getting pregnant have positive or negative effects on fetal development?
A
YES
2
Q
What is the periconception period?
A
period preceding, including and immediately following human conception
3
Q
What is the prenatal period?
A
period between conception and birth
4
Q
What is the perinatal period?
A
period immediately before and after birth
5
Q
What is the definition of pregnancy?
A
The state of carrying a developing embryo or fetus within the female body
6
Q
What is gestation?
A
total duration of pregnancy from fertilization to delivery
from conception = 38 weeks
from first day of last menstrual cycle = 40 weeks
7
Q
What does the first trimester of pregnancy consists of?
A
- important developmental milestones (fertilization, pre-embryonic period, embryonic period)
- development of organs and tissues (organogenesis)
-development and growth of placenta
8
Q
What is “fertilization” in the first trimester?
A
when sperm and ovum(egg) come to together in the fallopian tube
sperm penetrating the zona pellucida of egg causes the zone to become impermeable to other sperms penetrating it (cortical reaction)
9
Q
What is the order of fertilization in terms of what body of cells form
A
- zygote (2 gametes formed together, 46 chromos)
- Morula (solid cluster, has zona pellucida)
- blastocyst (dividing cells with central cavity filled with fluid)
10
Q
When does implantation of blastocyst occur during first trimester?
A
end of week 1
goes into endometrium (uterine lining)
11
Q
When can pregnancy be clinically detected?
A
following implantation
hCG —> in corpeus luteum
12
Q
What is Gastrulation in the embryonic period of early development?
A
when embryonic disc differentiates into 3 different germ layers which later on will form specific tissues
13
Q
what are the 3 germ layers that form during gastrulation?
A
- ectoderm (outer)
- mesoderm (middle)
- endoderm (inner)
14
Q
Is organogenesis during embryonic period a very critical period of development?
A
YES!
15
Q
What is organogensis?
A
formation of organs from germ layers following gastrulation
during weeks 4-8
embryo is most sensitive
16
Q
What does endoderm give rise to>
A
respiratory
thyroid cells
digestive
17
Q
what does mesoderm give rise to?
A
cardiac msucle
skeletal muscle
tubule cells
RBCs
smooth muscle
18
Q
what does ectoderm give rise to?
A
skin cells
Nervous system
pigment cells
19
Q
What is Placentation during the embyronic period of first trimester?
A
formation of the placenta
VITAL ORGAN DURING PREGNANCY
all the maternal-fetal exchange
20
Q
What happens during 2nd and 3rd trimester of pregnancy?
A
“fetal period”
- continued growth and differentiation of formed organs
growth in fetal size and length (2nd trimester)
growth in fetal weight (3rd trimester)
21
Q
What is parturition?
A
process of giving birth to offspring
- sequential, set of changes within myometrium, decidua and cervix
-occurs gradually over a period of days to weeks
22
Q
What is labor diagnosed with 2 things?
A
- presence of regular clinical contraction increasing in frequency and intensity
- progressive cervical effacement and dilation
23
Q
What are the hormones involved in parturition?
A
- progesterone
- estrogen
- oxytocin
- prostaglandins
- Corticotropin releasing hormone (CRH)
24
Q
What are the 5 steps to mechanisms involving parturition?
A
- functional progesterone withdrawl
- increased estrogen bioavailability
- increased response of myometrium to prostoglandins and oxytocin
- CRH and HPA axis activation
- uterine stretch
25
What does progesterone do in parturition?
-primary hormone
- sustains uterine quiesence (stillness) throughout pregnancy
- decreasing this at receptor level leads to initation of uterine contractions
26
What does estrogen do in parturition?
lots of this during pregnancy (hyperestrogenic state)
concentrations increase with gestational age
promotes cervical ripening --> Dilation!!
promotes myometrial changes --> uterine contractility (increases prostogladins, oxytocin, and myometrial gap junctions)
27
What does oxytocin do in parturition?
stimulates uterine contractions
stimulates placenta and decidua to produce prostoglandins
28
What does progstaglandins do in parturition?
stimulate uterine contractions
29
What does CRH do in parturition?
neuropeptide produced by hypothalmus
IMPORTANT TO HPA AXIS!!
stimulates ACTH secretion --> produces adrenal cortisol (GC) --> increases estrogen and prostroglandin
30
What is uterine stretch cycle ?
1. baby pushes against cervix --> stretch
2. stretch sends nerve signals to brain
3. brain stimulates post. pituitary to release oxytocin
4. oxytocin --> smooth muscle of uterus CONTRACTS
REPEAT! (Continous)
31
What are the 7 ways we can measure fetal health during pregnancy?
1. maternal weight gain
2. maternal cardiovascular adaptation
3. maternal insulin requirement
4. fetal growth profiles
5. genetic screening
6. placental health
7. uterine, placental, and umbilical blood flow
32
At time of birth how can they measure neonatal health? (7 ways)
1. gestational age at delivery
2. mode of delivery
3. birthweight centile
4. biometrics
5. organ function
6. feeding behaviours
7. nicu admission
33
What are the consequences of preterm birth?
increased morbidity and adult chronic disease
missed important fetal development milestones in utero and post natal
ex: not many organs fully developed
34
What is usually the main cause of preterm birth?
placental disease/dysfunction
35
What are the consequences of fetal growth restriction?
- due to IUGR (intrauterine growth hormone) restriction
- did not reach full growth potential due to compromised intrauterine environment
- quite small
- symmetrical --> risk of neurological damage , chromosomal abnormalities (down syndrome)
-assymetrical --> less fat and smaller abdominal organs ---> BRAIN SPARING
36
What is the main cause of fetal growth restriction?
compromised intrauterine environment
- abnormal uterine and/or umbilical artery flow
37
What is preclampsia?
where mother develops hypertension during pregnancy
can cause fetal and maternal mortality and morbidiity
can lead to eclampsia --> maternal seizures
38
What are the symptoms of preclampsia?
1. new onset of hypertension after 20 weeks gestation
2. proteinuria (protein in urine)
3. edema (water retention/swelling)
4. abnormal liver function (HELLP Syndrome)
39
Is there treatment for preclampisa?
- no
40
What are consequences of preclampsia to fetus?
pre-term birth
fetal growth restriciton
both affect developmental programming
can cause CVD and metabolic diseases later in life
41
What is gestational diabetes?
when you get diabetes during onset of pregnancy
tends to go away after pregnancy
inability to increase insulin secretion to compensate for pregnancy induced insulin resistance --> hyperglycemia
42
What are the consequences to gestational diabetes
short term and long term consequences on fetus (chronic diseases, obesity, T2DM, hyperglycemic, hyperinsulin)
43
What group of hormones is gestational diabetes in relation to
placental related hormones
44
What is the placenta?
vital organ of pregnancy
formed from both maternal and embryonic tissue
functions as lungs, liver, gut, kidneys, endocrine glands, and defensive barrier
provides oxygen and nutrients to fetus
removes waste products
produces hormones
PROTECTS FETUS
45
What is "decidualization"?
trnasformation of secretory endometrium to the decidua (uterine lining in pregnancy)
cells change from mesenchymal to epithelial ---> stores glycogen and lipids
46
What are** two structures **that are important in utero-placental circulation?
1. Chorionic villi
2. spiral arteries
47
What are chorionic villi and what do they do?
- help to maximize surface area contact with the maternal blood for nutrient and gas exchange
- in placenta
48
What are spiral arteries and what do they do?
- pierce decidual plate and enter intervillious spaces
- supply nutrients to placenta and fetus
49
why are spiral arteries remodelled by extravillous cytotrophoblast cells?
- replace smooth muscle and endothelium
- become highly dilated
- INCREASE flow
- DECREASE resistance
- not as spirally as before
50
What is Placenta Previa?
- when the placenta is abnormally placed by either totally covereing or close to internal os
-- sudden, painless vaginal bleeding
- c section required
51
What are the 3 ways placenta could be placed in placenta previa?
1. low lying
2. marginal
3. complete (right over internal os)
52
What are the risk factors to having placenta previa?
- abnormally developed uterus
- scarring of uterine wall from previous pregnancy
- large placenta
53
What is Placenta Accreta?
abnormal deep attachment of placenta
54
What is placenta increta>
placenta penetrates into myometrium
55
What is placenta Percreta?
penetrates entire myometrium to uterine serosa
56
What is the risk with Placenta accreta, increta, and percreta?
HEMORRHAGING
HYSTERECTOMY
57
What are the 5 different maternal-fetal exchanges?
1. diffusion
2. facilitated diffusion
3. osmosis
4. active transport
5. vesicular transport
58
What is diffusion?
- non polar molecules and fat soluble molecules
- flows [high] --> [low]
- not energy dependent
59
What is facilitated diffusion?
facilitated by transport molecules (carrier proteins/transmembrane proteins)
not energy dependent
60
what is osmosis?
soluble substances
H2O cannot cross through double lipid layer --> crosses placenta by aquaporines via the osmolar gradient
61
What is active transport?
transport AGAINST concentration gradient (low --> high)
energy dependent
amino acids go across placenta this way --> influenced by hormones
62
What is vesicular transport?
endocytosis, exocytosis
macromolecules are captured by microvilli and absorbed into cell or excreted from it
ex: immunoglobulins
63
What are the 5 functions of placenta?
1. GI --> continous transporters for nutrients
2. Endocrine --> different hormones and their roles
3. Lungs --> oxygen exchange and shunts
4. Barrier --> steroids, infection, xenobiotics, immunity
5. kidneys
64
What is the placental function of GI?
-placental nutrient supply is major determinant of intrauterine growth
- nutrient supply via circulatory system and parenteral nutrition, NOT fetal digestive tract
65
What are the 4 essential macronutrients for adequate fetal growth?
1. glucose
2. amino acids
3. free fatty acids
4. cholesterol
66
What does glucose do?
primary energy substrate for fetal AND placental growth
uses GLUT1 transporters via facilitated diffusion
67
What do amino acids do?
help with development of fetal tissue
68
What do Free fatty acids do?
help with brain development and fat accretion (CRITICAL IN FETAL GROWTH)
69
What are the 5 hormones of the endocrine system associated with function of placenta?
1. progesterone (P4)
2. estrogen
3. Placental lactogen
4. placental growth hormone
5. leptin
70
What is progesterone doing for placenta?
to maintain pregnancy
keeps uterine still throughout pregnancy
appetite stimulant
prevents mammary glands from being activated by prolactin before birth
levels fall at one point --> stimulate contractions
71
What does estrogen do in relation to placenta function?
for proliferation of endometrial cells
helps with mammary glands for developing and producing milk after birth
causes cervial ripening as concentration increases
cause contractility of uterus
72
What does placental lactogen do in relation to placental function?
- promotes fetal growth
- role in milk production
- look at slide 41
73
What does placetal growth hormone do?
stimulates glyconeogenesis, lipolyis, and anabolism in maternal organs
PROMOTES FETAL GROWTH
74
What does leptin do?
supresses food intake --> triggers us in our brain to believe we are full
when you are pregnant, mom is in leptin resistance
regulates fetal growth
75
How is the placenta equivalent to the lungs?
ensures fetal oxygen supply and co2 removal
fetus cant oxygenate its own blood!
deoxygenated blood --> in arteries from fetus to placenta
oxygenated blood --> in veins from placenta to fetus
- has shunts
76
What are the 3 shunts of the lungs for placental functions?
1. ductus venosus (by pass liver)
2. formamen ovale (by pass lung)
3. ductus arteriosus (by pass lung)
77
How does the placenta be a barrier to glucocorticoids?
stress hormone
regulates fetal exposure to it across pregnancy
protects from elevated levels of cortisol in maternal circulation
TOO MUCH STRESS COULD BE BAD
78
How is fetus vulnerable to infection via two routes?
1. ascend lower genital tract
2. from maternal blood to uterus
79
What is an effective barrier of placenta against infection?
intact syncutium (outermost layer of trophoblast) for vertical transmission
80
What is a xenobiotic ?
chemical substance that is foreign to body \
crosses placenta via faciltated diffusion or active transport
81
How does placenta reduce the transfer of xenobiotics?
it just does?
82
is immune system mature at time of birth of fetus?
NO
83
how can we counter protect fetus for immunity?
- maternal immune factors being transported via breast milk OR placenta
84
How is placenta like a kidney function?
-excretory functions
-removes waste products of fetal metabolism into maternal blood --> excreted by mom
85
Read 3rd lecture from slides
86
