Placenta Flashcards
Chorionic Villi
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Chorion Laeve/Smooth chorion
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Chorion Frondosum
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Preeclampsia: what is it, why it’s important to know, what causes it.
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When does regression of certain villi occur
7.5 weeks
Other name for trophecotderm
Cytotrophoblasts
Syncytiotrophoblast
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Primary Villi
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Secondary Villi
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Tertiary Villi
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Order of cell type/layers of placenta
Syncytiotrophoblast -> Trophectoderm -> Extraembryonic mesemchymal cells.
Anchoring Villi
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Transformed spiral arteries
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Endovascular trophoblast
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SGA/IUGR: What causes them and what are the consequence
Small for gestational age/ Intrauterine Growth Restriction
Mostly from poor fetal nutrition/lack of O2 supply
- > Inadequate depth of endovascular trophoblast?
- > Not enough transformed spiral arteries??
Trophoblast plug: Purpose and consequence
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Function of placenta
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Histiotrophic nutrition
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Structural change of placenta
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Decidua Basalis
Decidua underlying implantation site
Decidua Capsularis
Overlies implantation site
Decidua Peritalis
Surrounds remaining uterus
Placental Membranes
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Umbilical membranes and conents
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Whartons Jelly
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Bohr effect
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Functions of amniotic fluid
1) Buyoant medium for symmetrical growth
2) Protection from mild trauma
3) Prevents fetus adhesion to membranes (amniotic)
4) Allows fetal movement for muscle development
5) Allows foetal GI development (swallowing)
Source of amniotic fluid
1) Maternal blood ultrafiltrate
2) Urine from baby (500-1200mls/day)
Loss of amniotic fluid
1) Foetal Swallowing (500-1000mls/day)
2) Skin absorbtion prior to keratinization
Polyhydramnios
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Oligohydramnios
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Placenta prevents transmission of:
Measles
HepB
Malaria
Placenta does not prevent transmission of:
Rubella
HIV
CMV
Betamethasone
Drug given to fetus via mother
Prevents respiratory distress syndrome
Harmful drugs to fetus
Thalidomide
- In early gestation 20-70 days after LMP during organogenesis
- Causes limb reduction in babies
Some general drugs contraindicated in pregnancy:
Alcohol, crosses placenta and can cause foetal alcohol syndrome
Warfarin, causes growth abnormalities.
Recreational drugs, can cause IUGR.
hCG what is it
Gonadatropin similar a units different b unit.
What are hCG tests show?
If pregnant
If twins? (hCG porportional to amount of syncytiotrophoblasts)
Health of embryo/foetus
Functions of hCG:
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Where is progesterone synthesised in humans?
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How is PG synthesised in placent:
LDL-Cholesterol. Placenta has LDL-uptake receptors on surface.
Functions of PG
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Oestrogens in gestation, how are they produced?
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Where does placental estrogen and progesterone end up?
Mostly in maternal blood >85%
What causes pre eclampsia and whats treatment?
Triggered by something in placenta, delivery of placenta corrects hypertension and proteinuria.
Cardiac adaptations of pregnancy
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Causes and differentials of cardiac adaptations
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Haematological changes of pregnancy
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What increases risk of preeclampsia
A new partner and first pregnancy
Sexual intercourse with same partner for 12 months decreases risk of pre eclampsia.
Immune system in pregnancy/placenta.
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Abdominal wall and skin adaptations.
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