(8.2) Physiological Adaptation during Pregnancy

Question 1

How does the cardiovascular system adapt during pregnancy?

Answer 1

• Increased Heart Rate & Blood Volume & Stroke Volume & Cardiac Output
• Progesterone -> Vasodilation -> Hypotension

Question 2

What haematology changes occur during pregnancy? Hence, what may a pregnant woman be risk at?

Answer 2

• Increased Fibrinogen & Clotting Factors
• Reduced Fibrinolysis
• Risk of Thromboemobolism

Question 3

How does the respiratory system adapt during pregnancy? Hence, what may a pregnant woman be risk at?

Answer 3

• Progesterone -> Physiological Hyperventilation -> blow off extra CO2 produced by foetus
• Risk of Respiratory Alkalosis

Question 4

What may the action of Progesterone on smooth muscles cause complications to the Urinary system?

Answer 4

• Relax smooth muscles -> Urine stasis

- UTIs, Hydroureter, Pyelonephritis

Question 5

What hormone responsible the change observed in Thyroid hormones in pregnancy? Why is this change not noticed in free T4?

Answer 5

• Human Chorionic Thyrotrophin
• Increased T3, T4
• Also increas in Thyroxine Binding Globulin -> free T4 unchanged

Question 6

Describe the metabolic adaptations during pregnancy, including the hormones responsible for these.

Answer 6

Early

• Progesterone -> Lipogenesis
• Several hormones (Porlactin, hPL, Glucose, Cortisol) -> reduce Insulin sensitivity -> reduced Glucose Utilisation + increased Glucogenesis

Late
- hPL -> Lipolysis

hPL (human Placental Lactogen) = hCS (human Chorionic Somatotrophin)

Question 7

List what is tested during Antenatal screening?

Answer 7

• Blood: blood group + infection

- Urine: Pre-eclampsia? Eclampsia?

Question 8

What ausculatory changes can be heard in a pregnant women?

Answer 8

• Mitral regurgitation

- Displaced apex beat

Question 9

What may the action of Progesterone on smooth muscles cause complications to the GI system?

Answer 9

• Progesterone -> Smooth muscle relaxation
• Delayed emptying
• Biliary Stasis
• Pancreatitis

Question 10

What is the affect of pregnancy on GFR? How is this different to pre-eclampsia?

Answer 10

• Progesterone -> Vasodilation of afferent and efferent arterioles -> Increased GFR
• The reversed in Pre-eclampsia

Question 11

Why is there an increased risk of Anaemia in pregnancy?

Answer 11

• Increased Blood Volume

- Increased RBCs not as much

Question 12

Why are pregnant woman at risk of Thromboembolism? Why is this an issue with regard to its management?

Answer 12

• Long periods of sitting down
• Increased Fibrinogen & Clotting Factors
• Reduced Fibrinolysis
• Risk of Thromboemobolism
• Cannot give Wafarin, Teratogen

Question 13

What is Gestational Diabetes?

Answer 13

Human Chorionic Somatotrophin (a.k.a. Human Plancental Prolactin) ->

• Reduce Insulin sensitivity -> reduced Glucose Utilisation + increased Glucogenesis
• Lipolysis
• Disappears after pregnancy

Question 14

List two reasons why Ketoacidosis is common in pregnant woman?

Answer 14

• hCS -> Glucose availability -> Ketoacid

- Kidneys try to compensate the Respiratory Alkalosis caused by Physiological Hyperventilation

Question 15

Suggest two diseases of newborn child due to maternal immunity.

Answer 15

• Haemolytic Disease: attacked by maternal Rhesus antibodies that cross through Placenta
• Graves Disease/Thyroiditis: attacked or stimulated by maternal TSH receptors