Maternal Physiology

Question 1

Hematologic changes in pregnancy (Plasma, RBC, Reticulocyte, Hgb)

Answer 1

High Plasma
High RBC
High Reticulocyte
Low Hgb (<11g/dL)

Question 2

Iron requirements for pregnancy and distribution

Answer 2

1000mg

• 300mg for fetus and placenta
• 200 mg for GI losses
• 500mg for increase in RBC from pregnancy hypervolemia

Question 3

Physiology behind pregnancy hypercoagulant state

Answer 3

• Resistance to protein C
• Drop in protein S
• Low Antithrombin levels
• Low platelets

Question 4

Immunologic stages in pregnancy (Early, mid, parturition)

Answer 4

1) Early pregnancy - Pro-inflammatory
2) Mid pregnancy - Anti-inflammatory
3) Parturition - Pro-inflammatory

Question 5

Amount of T-cell increase (Leukocytosis) in pregnancy

Answer 5

T cells 25,000 u/L from 15,000 u/L

Question 6

Behavior of Cardiac Output (CO) in pregnancy and postpartum

Answer 6

CO Peaks in immediate postpartum and achieves baseline by 6-8 weeks

Question 7

Cardiovascular Changes in pregnancy (HR, Preload, MAP, SVR, TPR, BP)

Answer 7

Remember: Hypervolemia! More blood!

Increase in HR
Increase in Preload

Decrease in MAP
Decrease in SVR
Decrease in TPR
Decrease in BP

Question 8

Heart sounds observed in pregnancy

Answer 8

1) Exaggerated splitting in S1
2) Loud S3
3) Systolic murmur (90%)
4) Soft diastolic murlur (20%)
5) Continuous murmur (10%)

Question 9

ECG findings in Pregnancy

Answer 9

1) Slight left axis deviation
2) Q waves in leads II, III, avF
3) Flat/inverted T waves in leads III, V1-V3

Question 10

Thoracic cage changes in pregnancy (4-2-6)

Answer 10

> Diaphragm rises 4cm
Transverse diameter lengthens 2cm
Circumference increases by 6cm

Question 11

Respiratory changes in pregnancy

Changes in lung capacities

Answer 11

1) Increase in Inspiratory capacity (IC) due to increased TV and IRV

2) Decrease in Functinal residual capacity (FRC) due to decreased ERV and RV

Question 12

Respiratory changes in pregnancy

Lung capacities that remain the same

Answer 12

1) Total lung capacity (TLC = IRV + TV + ERV + RV)
2) Forced vital capacity (FVC = IRV + TV + ERV)

Question 13

Change in Total pulmonary resistance in pregnancy

Answer 13

Decrease in TPR (due to progesterone)

Question 14

Hormones contributing to vasodilation in pregnancy

Answer 14

High levels of prostacyclin and Nitric oxide

Question 15

% Increase in basal metabolic rate by the 3rd trimester

Answer 15

20% Increase in basal metabolic rate

Question 16

Energy requirements in the 3 trimesters of pregnancy

Answer 16

1st Trimester = 85kcal/day

2nd Trimester = 285 kcal/day

3rd Trimester = 475 kcal/day

Question 17

Average weight gain during pregnancy

Answer 17

12.5kg or 35-35lbs

Question 18

Glycemic changes in pregnancy (fasting and postprandial)

Answer 18

1) Mild fasting hypoglycemia
2) Post prandial hyperglycemia

Question 19

Insulin activity in pregnancy

Answer 19

Peripheral insulin resistance (dec insulin sensitivity) in order to maintain postprandial supply of glucose for neonate

Question 20

Fat metabolism in the 3 trimesters of pregnancy

Answer 20

1st-2nd Trimester = Anabolic (increased fat accumulation)

3rd Trimester = Catabolic (lipolysis) = HyperlipidemiaM

Question 21

Main energy source in late pregnancy

Answer 21

Lipids

Question 22

Leptin activity in pregnancy

Answer 22

Peak in 2nd trimester and plateau until term. Return to normal after delivery

Question 23

Electrolytes in pregnancy

Answer 23

Remember! Hypervolemia = altered osmoregulation

> Decreased serum Na
Decreased serum K
Decreased serum Ca
Decreased serum Mg
unchanged iCa

Question 24

Neonatal complication of excess iodine intake in pregnancy

Answer 24

congenital hypothyroidism via Wolff-Chaikoff effect

Question 25

Physiology behind heartburn in pregnancy

Answer 25

> Prolonged gastric emptying > Muscle relaxation of LES d/t progesterone > upward displacement of diaphragm

Question 26

Physiology behind intrahepatic cholestasis of pregnancy

Answer 26

Progesterone inhibiting contraction of the GB --> Bile stasis

Question 27

GFR Changes in pregnancy

Answer 27

Increased GFR (by 25% in 1st Trim and by 50% in 2nd Trim) remains elevated until term Increased RPF (by 80% in 1st Trim) declines in late pregnancy

Question 28

Reason behind physiologic metabolic acidosis in pregnancy

Answer 28

Decreased HCo3 by 4mEq/L) > Progesterone then stimulates respiratory center > Increased minute ventilation > compensating Respiratory alkalosis

Question 29

Leading cause of septic shock in pregnancy

Answer 29

Acute Pyelonephritis (usually during the 2nd trimester)

Question 30

Significant proteinuria in non-pregnant vs pregnant individuals

Answer 30

Non-pregnany proteinuria = >150mg/dL Pregnancy proteinuria = >300mg/dL

Question 31

Human Placental Lactogen (HPL) is produced by which cells

Answer 31

Syncytiotrophoblasts from the placenta

Question 32

When do levels of HPL peak in pregnancy

Answer 32

24-28 weeks logic behind timing of 75g OGTT

Question 33

Abdominal Landmark for the fundus of the uterus at 20 weeks

Answer 33

Umbilicus

Question 34

Abdominal Landmark for the fundus of the uterus at 36 weeks

Answer 34

Xiphoid process

Question 35

Physiology behind hyperpigmentation of areola and linea alba (becomes linea nigra) in pregnancy

Answer 35

Estrogen stimulates Anterior pituitary gland to release Melanocyte stimulating hormone