Maternal Physiology Flashcards
Hematologic changes in pregnancy (Plasma, RBC, Reticulocyte, Hgb)
High Plasma
High RBC
High Reticulocyte
Low Hgb (<11g/dL)
Iron requirements for pregnancy and distribution
1000mg
- 300mg for fetus and placenta
- 200 mg for GI losses
- 500mg for increase in RBC from pregnancy hypervolemia
Physiology behind pregnancy hypercoagulant state
- Resistance to protein C
- Drop in protein S
- Low Antithrombin levels
- Low platelets
Immunologic stages in pregnancy (Early, mid, parturition)
1) Early pregnancy - Pro-inflammatory
2) Mid pregnancy - Anti-inflammatory
3) Parturition - Pro-inflammatory
Amount of T-cell increase (Leukocytosis) in pregnancy
T cells 25,000 u/L from 15,000 u/L
Behavior of Cardiac Output (CO) in pregnancy and postpartum
CO Peaks in immediate postpartum and achieves baseline by 6-8 weeks
Cardiovascular Changes in pregnancy (HR, Preload, MAP, SVR, TPR, BP)
Remember: Hypervolemia! More blood!
Increase in HR
Increase in Preload
Decrease in MAP
Decrease in SVR
Decrease in TPR
Decrease in BP
Heart sounds observed in pregnancy
1) Exaggerated splitting in S1
2) Loud S3
3) Systolic murmur (90%)
4) Soft diastolic murlur (20%)
5) Continuous murmur (10%)
ECG findings in Pregnancy
1) Slight left axis deviation
2) Q waves in leads II, III, avF
3) Flat/inverted T waves in leads III, V1-V3
Thoracic cage changes in pregnancy (4-2-6)
> Diaphragm rises 4cm
Transverse diameter lengthens 2cm
Circumference increases by 6cm
Respiratory changes in pregnancy
Changes in lung capacities
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
Respiratory changes in pregnancy
Lung capacities that remain the same
1) Total lung capacity (TLC = IRV + TV + ERV + RV)
2) Forced vital capacity (FVC = IRV + TV + ERV)
Change in Total pulmonary resistance in pregnancy
Decrease in TPR (due to progesterone)
Hormones contributing to vasodilation in pregnancy
High levels of prostacyclin and Nitric oxide
% Increase in basal metabolic rate by the 3rd trimester
20% Increase in basal metabolic rate
Energy requirements in the 3 trimesters of pregnancy
1st Trimester = 85kcal/day
2nd Trimester = 285 kcal/day
3rd Trimester = 475 kcal/day
Average weight gain during pregnancy
12.5kg or 35-35lbs
Glycemic changes in pregnancy (fasting and postprandial)
1) Mild fasting hypoglycemia
2) Post prandial hyperglycemia
Insulin activity in pregnancy
Peripheral insulin resistance (dec insulin sensitivity) in order to maintain postprandial supply of glucose for neonate
Fat metabolism in the 3 trimesters of pregnancy
1st-2nd Trimester = Anabolic (increased fat accumulation)
3rd Trimester = Catabolic (lipolysis) = HyperlipidemiaM
Main energy source in late pregnancy
Lipids
Leptin activity in pregnancy
Peak in 2nd trimester and plateau until term. Return to normal after delivery
Electrolytes in pregnancy
Remember! Hypervolemia = altered osmoregulation
> Decreased serum Na
Decreased serum K
Decreased serum Ca
Decreased serum Mg
unchanged iCa
Neonatal complication of excess iodine intake in pregnancy
congenital hypothyroidism via Wolff-Chaikoff effect
Physiology behind heartburn in pregnancy
> Prolonged gastric emptying
Muscle relaxation of LES d/t progesterone
upward displacement of diaphragm
Physiology behind intrahepatic cholestasis of pregnancy
Progesterone inhibiting contraction of the GB –> Bile stasis
GFR Changes in pregnancy
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
Reason behind physiologic metabolic acidosis in pregnancy
Decreased HCo3 by 4mEq/L)
> Progesterone then stimulates respiratory center > Increased minute ventilation > compensating Respiratory alkalosis
Leading cause of septic shock in pregnancy
Acute Pyelonephritis (usually during the 2nd trimester)
Significant proteinuria in non-pregnant vs pregnant individuals
Non-pregnany proteinuria = >150mg/dL
Pregnancy proteinuria = >300mg/dL
Human Placental Lactogen (HPL) is produced by which cells
Syncytiotrophoblasts from the placenta
When do levels of HPL peak in pregnancy
24-28 weeks
logic behind timing of 75g OGTT
Abdominal Landmark for the fundus of the uterus at 20 weeks
Umbilicus
Abdominal Landmark for the fundus of the uterus at 36 weeks
Xiphoid process
Physiology behind hyperpigmentation of areola and linea alba (becomes linea nigra) in pregnancy
Estrogen stimulates Anterior pituitary gland to release Melanocyte stimulating hormone
