Physiology of Pregnancy and Lactation

Question 1

The placenta is derived from which tissues?

Answer 1

Trophoblast and decidual

Question 2

Placental villi are formed from what?

Answer 2

The embryo sending capillaries into the syncytiotrophoblast projections

Question 3

What provides early nutrition for the embryo?

Answer 3

Invasion of trophoblastic cells into the decidua

Question 4

The villi extended into the uterine wall contain what?

Answer 4

Blood vessels from the embryo

Question 5

How does circulation within the intervillous space act?

Answer 5

Arteriovenous shunt

Question 6

Which structure plays the role of the foetal lungs?

Answer 6

Placenta

Question 7

Oxygen diffuses from the foetal/maternal circulation into the foetal/maternal circulation

Answer 7

From the maternal into the foetal circulation

Question 8

Oxygen saturated blood returns to the foetus via which structure?

Answer 8

Umbilical vein

Question 9

Which three factors facilitate the supply of the foetus with oxygen?

Answer 9

Foetal Hb
Higher Hb concentration in foetal blood
Bohr effect

Question 10

How does water diffuse into the placenta?

Answer 10

Along its osmotic gradient

Question 11

How does glucose enter the placenta?

Answer 11

Simplified transport

Question 12

What is the effect of human chorionic gonadotropin?

Answer 12

Prevents involution of the corpus luteum

Question 13

Give some effects of human chorionic somatomammotropin

Answer 13

Protein tissue formation
Increased foetal glucose
Breast development

Question 14

Give some effects of increased progesterone levels during pregnancy

Answer 14

Development of decidual cells
Decreased uterus contractility
Prepares for lactation

Question 15

Give some effects of increased oestrogens during pregnancy

Answer 15

Enlargement of uterus
Breast development
Relaxation of ligaments

Question 16

Which oestrogen provides an indicator for foetal vitality?

Answer 16

Oestriol

Question 17

CRH released from the placenta can cause maternal hypertension and insulin resistance. How?

Answer 17

As it increases ACTH levels increasing aldosterone and cortisol

Question 18

What effect can placental HCG have on the mother?

Answer 18

Hyperthyroidism

Question 19

Increased calcium demands from the placenta can lead to which condition?

Answer 19

Hyperparathyroidism

Question 20

Give some of the cardiovascular changes that occur during pregnancy

Answer 20

Increase in cardiac output
Heart rate increases
Blood pressure falls (during second trimester)

Question 21

Why does cardiac output increase during pregnancy?

Answer 21

Due to demands of uteroplacental circulation

Question 22

Why does cardiac output decrease during the last 8 weeks of pregnancy?

Answer 22

As the uterus compresses the inferior vena cava

Question 23

Give some haematological changes that occur during pregnancy

Answer 23

Plasma volume increases
Erythropoesis (RBC) increases
Hb decreases

Question 24

What causes lung function to change during pregnancy?

Answer 24

Progesterone increases

Enlarging uterus

Question 25

What respiratory changes occur during pregnancy?

Answer 25

Lower CO2 levels | O2 consumption increases

Question 26

What changes take place in the renal system during pregnancy?

Answer 26

GFR increases Increased re-absorption ions and water Increased urine formation

Question 27

What is the definition of pre-eclampsia?

Answer 27

Pregnancy induced hypertension + proteinuria

Question 28

Give some risk factors for pre-eclampsia

Answer 28

``` Hypertension Diabetes Autoimmune disease Renal disease FHx PMHx ```

Question 29

What occurs in eclampsia?

Answer 29

Vascular spasms Extreme hypertension Chronic seizures Coma

Question 30

How is eclampsia treated?

Answer 30

Vasodilators and C-section

Question 31

What is the average maternal weight gain in pregnancy?

Answer 31

6kg

Question 32

How many extra calories does the mother need per day during pregnancy?

Answer 32

300

Question 33

When does the mother's anabolic phase occur?

Answer 33

Weeks 1-20

Question 34

What occurs in the mother's anabolic phase?

Answer 34

Normal/increased sensitivity to insulin Lower plasmatic glucose level Lipogenesis Growth of breasts/uterus

Question 35

What occurs in the mother's catabolic phase?

Answer 35

Maternal insulin resistance Increased nutrient transport to placenta Lipolysis

Question 36

Give some common nutritional needs in pregnancy

Answer 36

Folate Vit D supplements High protein supplements Iron

Question 37

During parturition, the oestrogen:progesterone ratio increases/decreases

Answer 37

Increases - oestrogen increases contractions

Question 38

Which pituitary hormone increases contractions?

Answer 38

Oxytocin

Question 39

The stretch of which structure increases contractility

Answer 39

Cervix

Question 40

Which hormone induces oxytocin receptors on the uterus?

Answer 40

Oestrogen

Question 41

Outline the positive feedback role of oxytocin in labour

Answer 41

Oxytocin stimulates placenta to make prostaglandins which stimulates more vigorous contractions of the uterus which increases oxytocin production

Question 42

What are the three stages of labour?

Answer 42

Cervical dilation Passage through birth canal Placental expulsion

Question 43

Which hormone is important in the growth of the ductile system?

Answer 43

Oestrogen

Question 44

Which hormone is important in development of the lobule-alveolar system?

Answer 44

Progesterone

Question 45

Which hormone stimulates milk production?

Answer 45

Prolactin

Question 46

Which hormone helps in milk secretion?

Answer 46

Oxytocin