Physiology in Pregnancy Flashcards
1
Q
What changes happen to a women’s breasts during pregnancy?
A
- Increased size and vascularity (warm, tense and tender)
- Increased pigmentation of the areola and nipple
- Secondary areola appears
- Montgomery tubercules appear on the areola
- Colostrum like fluid can be expressed from the end of the 3rd month
2
Q
What happens to the cardiovascular system during pregnancy?
A
- Increased circulating blood volume
- Systemic vascular resistance falls
- Increased blood flow
- Increased cardiac output (due to increased stroke volume)
- Increased heart rate
- 25% reduction of cardiac output in the supine position
- Increased oxygen consumption
3
Q
What cardiovascular changes occur during labour?
A
- Autotransfusion of contractions
- Pain: increased catecholamines
- CO increases by 10% in labour and by 80% in first post delivery hour
4
Q
What cardiovascular changes occur after birth?
A
- Returns to normal after 3 months
- Blood volume decreases by 10% 3 days post delivery
- BP initially falls then increases again 3-7 days later
- SVR increases over first 2 weeks to 30% above delivery levels
- HR returns to normal over 2 weeks
- CO begins to fall after the first hour and then over the next 24 weeks
5
Q
What happens to the respiratory system during pregnancy?
A
- 20% increase in oxygen demand
- 40-50% increase in minute ventilation
- Increased RR and increased tidal rate
- Decreased functional residual capacity
- PEFR and FEV1 are unchanged
- Decreased PCO2
6
Q
What happens to the renal system during pregnancy?
A
- Massive dilatation of the urinary collecting system
- Increased renal plasma flow (60-80% by end of 2nd trimester)
- Increased GFR and creatinine clearance
- Protein excretion increases
- Microscopic haematuria may be present and 80% develop oedema
- Glycosuria is common
- Urate levels increase with gestation
- Urea and creatinine levels decrease
7
Q
What haematological changes happen during pregnancy?
A
- Plasma volume increases
- Hg, Hcrit and RCC decrease
- No change in MCV or MCHC
- Decreased platelet count
- 2-3 fold increase in requirement for iron
- 10-20 increase in folate requirements
- WCC increases
- Hypercoagulable