Definition
- Physiological changes during pregnancy are maternal hematological, cardiovascular, respiratory, renal, GI and endocrine adaptations that increase oxygen and nutrient delivery to the fetus and remove fetal waste.
Total blood volumeincreases about 40% above pre-pregnant levels
Changes in Blood Volume and Hematological Changes
Hematological changes in pregnancy
Parameter
Plasma volume
- Change
- ↑ about 40%, mainly from ECF volume expansion, increases early
Red cell mass
- Change
- ↑ about 20 to 30%, increases slowly after 16 weeks gestation
Red cell count
- Change
- Low, from hemodilution: physiological anemia of pregnancy
WBC count
- Change
- Moderate leucocytosis (neutrophilia), left shift in Arneth count
Platelet count
- Change
- Remains almost normal
Fibrinogen
- Change
- ↑ 2 to 4 times