<prompt> All of the following may be observed in a normal pregnancy EXCEPT:Fall in serum iron concentrationIncrease in serum iron binding capacityIncrease in blood viscosityIncrease in blood oxygen carrying capacity  <response>: Blood thins out in pregnancy due to the hemodilution of pregnancy. The increase in Blood volume 30-45 is relatively greater than that of red cell mass 20-30 resulting in hemodilution and a decrease in haemoglobin concentration. Fibrinogen as well as factors VII , IX, X and XII increase markedly. These changes tend to prevent excessive bleeding at delivery. Pregnancy is a hyper-coagulable state thus, but this is not synonymous with Increased viscosity . 