Chemotherapies and radiotherapy can temporarily impair the production of certain blood cells. For that reason, your blood count is regularly tested.
The number of white blood cells (leucocytes) may decrease. Because these cells are important for your defence against infection, your susceptibility to infection may be increased during this period.
The number of platelets in your blood may decrease. These cells are important for blood clotting. You may therefore have a greater tendency to bleed during this period.
The number of red blood cells (erythrocytes) decreases (anaemia). These cells are responsible for transporting oxygen in the blood. Anaemia can lead to increased fatigue and breathlessness on exertion.