white cell count (WCC) in pregnancy
Last reviewed 01/2018
During pregnancy:
- blood volume:
- there is an increase in the total blood volume, the plasma volume and the red cell volume during pregnancy. The total blood volume increases by about 30-40% by about 34 weeks of pregnancy
- there is a relative increase in plasma with respect to red cells - 45% increase in plasma versus 18% increase in red cells respectively. This imbalance causes a haemodilution
- white cell count:
- during pregnancy there is also an increase in white cells from about 7 x 10^9 to 15 x 10^9 per litre solely due to a neutrophilia - note that other causes of a raised neutrophil count must be excluded
- platelet count:
- there is also a rise in the number of platelets from 180 x 10^9 to over 300 x 10^9 during pregnancy. This rise continues in the puerperium
- ESR:
- erythrocyte sedimentation rate increases during pregnancy due to an increase in fibrinogen and globulin levels; there is however a fall in the amount of albumin