Physiological Changes in Pregnancy

Question 1

How does energy demands change in pregnancy?

Answer 1

14% increased demand:

• Increased fat storage (4kg stored)
• Less protein requirement
• Insulin sensitivity decreases
  
  • Mother absorbs less glucose
  • More glucose available for baby

Question 2

How does the anatomy change in pregnancy?

Answer 2

• Striae gravidarum (abdomen)
• Stria distensae (medial thigh)
• Linea nigra
• Chloasma gravidarum (mask of pregnancy)

Question 3

What cardiac changes occur in pregnancy?

Answer 3

• CO increased 50%
• SV increased 35%
• Less peripheral resistance - progesterone
• HR increased 15-25%
• LAD on CXR due to compensatory LVH

Question 4

What respiratory changes occur in pregnancy?

Answer 4

• Tidal volume increased 30-50%
  
  • Increased minute ventilation
  • Feeling of breathlessness
• FRC decreases
• RR does not change

Question 5

What renal changes occur in pregnancy?

Answer 5

• More aldosterone created = fluid retention
• GFR increases in 1^st trimester

Question 6

What haematological changes occur in pregnancy?

Answer 6

• Macrocytosis
• Neutrophilia
• Thrombocytopenia
• Dilutional anaemia
• Increased VWF, F7, F8, fibrinogen, PAI-1/2
• Decreased protein S

Question 7

What endocrinological changes occur in pregnancy?

Answer 7

• Biggest increase = oestriol
• Less increase = oestrone, oestradiol
• LH and FSH supressed