The placenta

Question 1

Roles of placenta

Answer 1

Foetal lungs/kidneys/GI tract
Protection
Hormones

Question 2

2 parts of blastocyst

Answer 2

Inner cell mass - baby

Trophoblast - placenta

Question 3

Syncytiotrophoblast

Answer 3

Direct contact with maternal blood
Outer layer of multiple fused trophoblast cells (specialised systems for maternal to fetal transport, barrier to unwanted material and hormone secretion)

Question 4

Cytotrophoblast

Answer 4

Inner layer with several specialised functions: proteolytic enzyme secretions (acts on decidua), endometrial invasion, villous formation, angiogenesis

Question 5

Blood supply to uterus

Answer 5

Aorta - internal iliac - uterine - ovarian - arcuate - radial - basal - spinal

Question 6

How do uterine blood vessels change in pregnancy?

Answer 6

As pregnancy develops, spiral arteries funnel, generating a wider outflow into the intervillous space

Question 7

Arteries to placenta

Answer 7

2, deoxygenated

Question 8

Veins to placenta

Answer 8

1, oxygenated

Question 9

Protrusions of placenta

Answer 9

Cotyledon

Question 10

hCG in pregnancy

Answer 10

Produced from blastocyst

Support pregnancy in 1st trimester - CL

Question 11

Progesterone in pregnancy

Answer 11

Placenta from 12 weeks

Question 12

Human placental lactose

Answer 12

Anti-insulin = more glucose for foetus

Question 13

O2 transfer from mother

Answer 13

Small right shift = O2 unloading

Question 14

O2 transfer to foetus

Answer 14

Left shift = O2 uptake

Question 15

Placental barrier

Answer 15

Microbiological safety barrier
Less efficient in early pregnancy
Maternal antibodies = immune protection

Question 16

Why doesn’t the mum attack baby

Answer 16

Phosphocholine secreted by placenta

Suppression of cytotoxic T cells

Question 17

Which pregnancy does Rhesus affect mother?

Answer 17

Second

Question 18

Which antibodies are ABO?

Answer 18

IgM - doesn’t cross placenta

Question 19

RhD antibodies

Answer 19

IgG

Question 20

Can RhD antibodies cross placenta?

Answer 20

Yes, they are small

Question 21

If Rh+ and Rh- parents have baby will it be + or -

Answer 21

+ve

Question 22

What is given to Rh-ve mothers?

Answer 22

Anti-D in pregnancy

Question 23

When is Rh -ve mother given anti-D?

Answer 23

28/34

Within 72 hours if baby is Rh +ve

Question 24

Placenta praaevia

Answer 24

Placenta lies across cervical os

Question 25

Placental abruption

Answer 25

Bleeding between placenta and uterus

Question 26

Prolapsed cord

Answer 26

Cord bulges through cervix

Question 27

Pre-eclampsia

Answer 27

Placenta issue in baby and mum

Question 28

Grade I - grade IV placenta praevia

Answer 28

Grade 1 = none, grade 5 = fully covered

Question 29

Symptoms of placenta praevia

Answer 29

Bleeding during pregnancy | Painless

Question 30

Symptoms of placental abruption

Answer 30

Painful Bleeding can be revealed or concealed Life-threatening for foetus

Question 31

Cord prolapse

Answer 31

Membranes rupture | Foetal head compresses cord = umbilical

Question 32

Maternal symptoms of pre-eclampsia

Answer 32

``` Hypertension Fluid retention Coagulopathy Renal damageConvulsions Liver damage ```

Question 33

Fetal symptoms of pre-eclampsia

Answer 33

Growth retardation