Pregnancy

Question 1

Define the risks associated with the 1st trimester

Answer 1

• chromosomal abnormalities/placental problems leading to miscarriage
• susceptibility to insult leading to congenital abnormalities is highest

Question 2

What weeks constitute the 1st trimester?

Answer 2

0-13

Question 3

What weeks constitute the 2nd trimester?

Answer 3

14-26

Question 4

What is the main feature of the 1st trimester?

Answer 4

most structural development (embryology) of the fetus occurs

Question 5

What is the viability limit?

Answer 5

24 weeks

Question 6

Define the risks of 2nd trimester

Answer 6

safest time for baby and mother - however fetus becomes viable at 24 weeks so there are risks of preterm birth

Question 7

What maternal changes occur in the 2nd trimester?

Answer 7

Increased weight
Increased blood volume
Increased blood clotting tendency
Decreased blood pressure
Altered fluid balance
Altered joints

Question 8

What are the features of the second trimester?

Answer 8

• lots of maternal changes
• uterine stretch
• prog and est levels continue to increase

Question 9

What weeks constitute the 3rd trimester?

Answer 9

27-39

Question 10

What are the features of the 3rd trimester?

Answer 10

• in utero maturing of brain, lungs, GI tract, immune system
• HUGE growth - 2kg increase
• uterine system preps for delivery

Question 11

List some maternal changes that occur in the 1st trimester

Answer 11

Altered emotional state 
Altered hormones
Altered brain function 
Altered immune system 
Altered appetite

Question 12

Describe hCG levels during pregnancy

Answer 12

peaks around week 9 and rapidly falls

Question 13

Describe the levels of estrogen progesterone and placental lactogen during pregnancy.

Answer 13

All increase 100-1000 fold compared to non-pregnant women. Progesterone increases the MOST. est and lactogen increase the same amount.

Question 14

List the 5 main placental functions

Answer 14

Separation of maternal and fetal system 
Exchange of nutrients and waste products
Biosynthesis 
Immunoregulation
Connection by anchoring pregnancy in place

Question 15

What structures supply blood to the foeto-placental unit?

Answer 15

spiral arteries

Question 16

name the functional unit of the placenta

Answer 16

Cotyledon

Question 17

describe oxygenation of blood in umbilical veins and umbilical arteries

Answer 17

Umbilical veins carry OXYGENATED blood because they are running TOWARD the fetal heart

Umbilical arteries carry DEOXYGENATED blood because they are running AWAY from the fetal heart

(just like pulmonary veins/arteries)

Question 18

Summarise how the placenta develops

Answer 18

1. implantation of conceptus into endometrial epithelium
2. synctiotrophoblast = outer layer of conceptus contain fluid filled lacunae
3. inner layer of conceptus.= cytotrophoblasts
4. STB projections embed in endometrium
5. STB lacunae fill with maternal blood
6. CTB expands into STB becoming primary chorionic villi
7. mesoderm line the villi becoming secondary chorionic villi
8. embryonic vessels form in mesoderm becoming teriary chorionic villi
9. CTB shell
10. week 6 CTB invade spiral arteries
11. week 10-12 CTB plug break down to expose placenta to full maternal blood flow

Question 19

distinguish between miscarriage and still birth

Answer 19

MC < 24 weeks

SB > 24 weeks