Increase seen in plasma volume in pregnancy: March 2010

Ans. D: 40-50% The most striking maternal physiologic alteration occuring during pregnancy is the increase in the blood volume. The magnitude of the increases varies according to the size of woman, the number of pregnancies she has had, the number of infants she has delivered, and whether there is one or multiple fetuses. The increases in blood volume progress until term; the average increase in volume at term is 45-50%. The increase is needed for extra blood flow to the uterus, extra metabolic needs of fetus and increased perfusion of others organs, especially kidneys. Extra volume also compensate for maternal blood loss delivery. Plasma volume increases during pregnancy. The rate of increase almost parallels to that of blood volume but the maximum is reached to the extent of 50%.Total plasma volume increases to the extent of 1.25 litres.