Pregnancy

Question 1

What are the features and risks of the first trimester?

Answer 1

0-13 weeks

Very risky

If you pass this, then 90% reach term

Question 2

What are features and risks of second trimester?

Answer 2

13-27 weeks

Question 3

What is the point of viability?

Answer 3

Modern technology - 22 weeks

50% chance of survival at 25 weeks

Question 4

What are the features and risks of third trimester?

Answer 4

up to 39/40 weeks

Question 5

What are the maternal changes associated with pregnancy?

Answer 5

Increased weight - more so in 2nd and 3rd

Increased/altered hormones - HCG (peaks in first trimester) , increased oestrogen and progesteron, HPL

Increased blood clotting

Decreased blood pressure

Increased basal body temp

Increased breast size

Increased vaginal mucus secretion (clear)

Increased nausea and vomiting

Altered brain function

Altered apetite

Altered fluid balance and urinary frequency

Altered emotional state

Altered joints

Altered immune system

Question 6

What may cause nausea and vomiting?

Answer 6

Correlated with high level of HCG so may be causative link

Question 7

What are the key kidney changes in pregnancy?

Answer 7

Increased fluid retention and higher plasma volume

pass smaller volumes of urine more frequently

Question 8

What may cause the altered immune response in pregnancy?

Answer 8

1. factors produced to suppress immune system e.g. decrease Th1 and Th2 response
2. placenta expressed unusal HLA on surface that is in contact with maternal tissues - HLA-G

Question 9

What does embryo mean?

Answer 9

the baby up to 8 weeks of development

Question 10

What timing is used by gynaecologists?

Answer 10

Last menstrual period

Question 11

What timing is used by embryologists?

Answer 11

IVF

Point of fertilisation

2 weeks difference from LMP

Question 12

In which trimester does the baby gain the most weight?

Answer 12

3rd trimester
2nd
1st

Question 13

What develops late in pregnancy?

Answer 13

lungs, digestive system, immune system, brain (continous)

Question 14

What are the functions of the placenta?

Answer 14

1. exchange of nutrients
2. connection (anchorage)
3. Separation
4. Biosynthesis
5. Immunoregulation

Question 15

What is the primary subunit of placenta?

Answer 15

Placental villus

Question 16

What is different about the vascular system in placenta?

Answer 16

Arteries - deoxygenated blood

Veins - oxygenated blood

because it acts as lungs for the foetus

Question 17

Where does the placenta develop from?

Answer 17

Syncytiotrophoblast cells contain lacunae

Question 18

Describe the development of placenta

Answer 18

Cytotrophoblast cells proliferate

First columanr structure formed (cytotrophoblast column) then branching

At the centre of each villus, mesenchymal cells - villus vascualr system develops from here

Question 19

How does the placenta change by term

Answer 19

Fewer cytotrophoblasts

Maximise efficacy of nutrient transfer

Question 20

What provides the nutrients to placenta and baby in first trimester?

Answer 20

Decidual glands

Question 21

What are the spiral arteries blocked by?

Answer 21

Cytotrophoblast cells

Question 22

When does the cytotrophoblast plug break down?

Answer 22

10-12 weeks GA

Risky time frames as placenta is not fully anchored

Question 23

What is the remodelling of spiral arteries?

Answer 23

By cytotrophoblasts

vascular endothelium, smooth muscle cells replaced

widens the spiral arteries to support growing baby

begins during first trimester and finishes until 16-18 weeks of gestation

Question 24

What regulated the growth of the placenta?

Answer 24

autocrine - produces own GF

Maternal decidua - restricts growth