Session 6 - Pregnancy

Question 1

In the third month, what is the arrangement of the villi?

Answer 1

Villi move to only be at the placental end. So chorion frondosum at that end and chorion laeve elsewhere

Question 2

When does the placenta start to develop

Answer 2

2nd week (first organ!)

Question 3

In week 2 what structures will there be

Answer 3

Syncytiotrophoblast, cytotrophoblast, bilaminar disk (epiblast and hypoblast)

Question 4

What happens at day 6

Answer 4

Implantation

Question 5

What happens at day 9

Answer 5

Blastocyst is embedded in endometrium

Question 6

Amniotic cavity is formed by the

Answer 6

epiblast

Question 7

What becomes the umbilical cord?

Answer 7

The connecting stalk

Question 8

What is the area surrounding the epiblast/hypoblast

Answer 8

Chorionic cavity

Question 9

What happens to the 3 sacs (chorionic, yolk, and amniotic)

Answer 9

Yolk sac regresses, chorionic gets smaller and amniotic expands

Question 10

Describe primary secondary tertiary villi

Answer 10

Primary are just outgrowths of trophoblast, secondary mesenchyme has invaded into core, tertiary fetal vessels have invaded mesenchyme core

Question 11

what does the endometrium transform into in presence of conceptus

Answer 11

decidua capsularis

Question 12

what happens if the blastocyst can’t implant enough

Answer 12

Placental insufficiency

Question 13

Compartments of the placenta are called

Answer 13

Cotyledons

Question 14

How is the villus different in the 3rd trimester

Answer 14

Fewer cytotrophoblast, barrier is thinner

Question 15

Name hormones produced by placenta

Answer 15

hCG (protein), progesterone and oestrogen (steroid)

Question 16

How many umbilical arteries/veins

Answer 16

2 arteries (carry deoxy) and one vein (oxy)

Question 17

When and what is hCG produced by

Answer 17

In first 2 months by synctiotrophoblast

Question 18

What is choriocarcinoma

Answer 18

Malignancy of chorionic membrane, lots of hCG produced

Question 19

When does placenta take over progesterone production

Answer 19

11th week

Question 20

How do progesterone and hCS/hPL influence metabolism

Answer 20

Progesterone increases appetite, hCS/hPL increases glucose availability to fetus

Question 21

What substance needs facilitated diffusion across the placenta

Answer 21

Glucose

Question 22

Passive immunity through which Ig

Answer 22

IgG

Question 23

How are amino acids transferred across placenta

Answer 23

Active transport

Question 24

How is IgG transferred across placenta

Answer 24

Endo/Exocytosis

Question 25

Haemolytic disease of the newborn?

Answer 25

So baby is rhesus positive, mother is rhesus negative. In first pregnancy if blood mixes she develops antibodies to rhesus pos. In second pregnancy antibodies cross placenta and attack babe

Question 26

Name drugs bad for baby

Answer 26

Thalidomide, ACE inhibitors, warfarin

Question 27

When is embryo most sensitive to teratogens

Answer 27

3-8 weeks

Question 28

What effect do teratogens have in pre-embryonic period

Answer 28

lethal

Question 29

After the embryonic period, the risk of teratogens causing structural defects are very low except…

Answer 29

CNS

Question 30

When are the embryonic and fetal periods

Answer 30

Embryo 3-8, fetus 9-38

Question 31

Which infections are important in pregnancy

Answer 31

Rubella, influenza, CMV, listeria, TB, chickenpox, leishmania

Question 32

Is gas exchange across placenta flow limited or diffusion limited

Answer 32

Flow limited