Antenatal Care: Pregnancy Physiology

Question 1

Describe the anatomic and physiologic changes in the cardiovascular system during pregnancy

Answer 1

• The heart is displaced left and upwards + it is rotated along its axis.
• Heart sounds are a little different in pregnant women.
• Systemic Vascular resistance DECREASES
• Mean Arterial pressure DECREASES
• Heart rate INCREASES
• Cardiac output INCREASES (15-40%)

Question 2

Identify the hematological changes in pregnancy

Answer 2

• Erythrocyte levels and blood plasma levels INCREASE
• Blood volume INCREASES 40-45% above non-pregnant women.
• Physiologic Anemia
• Iron requirements INCREASE (get in the diet but some women might need supplements).
• Pregnancy is an immunodeficient state.
• Hypercoagulability state - prone to DVT and PE.
• blood thickens
• Huge problem in c-section when the risk of DVT and PE already are increased

Question 3

Explain the association between pregnancy and deep venous thrombosis/pulmonary embolism

Answer 3

• hypercoagulability increases in pregnancy
• blood thickens

Question 4

Describe the anatomic and physiologic changes in the pulmonary system during pregnancy

Answer 4

• diaphragm pushed upwards by the growing uterus

Question 5

What happens to the FRC (functional residual volume) in pregnancy?

Answer 5

decreases

Question 6

What happens to the TLC (total lung capacity)?

Answer 6

Remains unchanged

Question 7

What happens to the ERV (Expiratory reserve volume)?

Answer 7

decreases

Question 8

What happens to the residual volume?

Answer 8

decreases

Question 9

What happens to the tidal volume and minute ventilation?

Answer 9

Increases

Question 10

Describe the anatomic changes in the gastrointestinal system during pregnancy

Answer 10

• Stomach and intestines are displaced by the
  growing uterus.
• Decreased tone of the Lower esophageal sphincter.
• This leads to acid reflux in the 1st trimester and 3rd (sometimes).

Question 11

Describe the anatomic and physiologic changes in the renal system during pregnancy

Answer 11

• Increase in size of the kidneys due to the increase in blood volume.
• Hydronephrosis due to the compression of the ureter (mainly right) by the growing uterus.
• as the uterus grows it rotates to the right.

Physiological changes:
- Serum creatinine decreases
- Creatinine clearance increases
- GFR increases
(may see glucose in the urine due to increased GFR).
Maybe a sign of gestational diabetes.

Question 12

Explain the increased risk of urinary tract infections during pregnancy

Answer 12

• Due to hydronephrosis (compression of the ureter by the growing uterus).
• Progesterone slows down the motility of the ureter.

Question 13

Identify the metabolic adaptations in pregnancy

Answer 13

• Increased BMR - by 10-20%
• Due to an increase in growth and cell turnover that takes place during pregnancy.
• As a result, there is an increase in caloric demand.
• This changes throughout the pregnancy.
• increases as the patient gets further along in the pregnancy.
• Increase in water retention - 6.5 L
  Plasma osmolality decreases - edema

Question 14

Recall the hormonal changes in pregnancy

Answer 14

• Increase in Progesterone and estrogen
• aldosterone and renin increases
• Relaxin increases ( responsible for loosening the ligaments in hips and pubic symphysis).

Question 15

Describe the development of the breast and reproductive system during pregnancy

Answer 15

• Breasts get bigger (normal for women to go up 2 cup sizes)
• Breats and areola increase
• Uterus increases in size - up to 5L/ 1100g by the full term.
• Cervix softens
• Eversion of endocervical glands - common reason for bleeding throughout pregnancy.

Question 16

List the skin changes during pregnancy

Answer 16

• Stretch marks
• Melasma (pregnancy mask)
• Melasma is a skin condition that causes patches and spots, usually on the face, which are darker than your natural skin tone.
• Linea nigra - black line extending between belly and fundus.
  Due to an increase in melanocytes during pregnancy.