Normal Platelet Count

Platelets are minute cells with irregular shape that are present in the blood of mammals. These cells are formed by the fragmentation of bone marrow cells called megakaryocytes. These cells lack nucleus and have a lifespan of around eight to twelve days. Blood platelets play an important role in stopping bleeding by forming blood clots. While a low level of platelets in the blood may result in excessive bleeding, high platelet count may cause formation of blood clots, which can block blood vessels and result in heart attacks, stroke and blocked blood vessels in arms and legs. Hence, a normal platelet count is necessary to avoid such conditions. Platelet count test is conducted as a part of the complete blood count and is often required to be performed, in case of bleeding disorders or bone marrow diseases.

Normal Platelet Levels

In case of a normal healthy individual, the normal platelet level can range between 150000 and 450000 per μl (micro liter) of blood. According to some studies, almost 95% of healthy people have platelet values within this range. Even though a count which is above or below this range is considered abnormal, some people with small variations are found to be perfectly healthy. However, drastic variations from the normal platelet count can be fatal. Low platelet count (thrombocytopenia) and high platelet count (thrombocytosis) can cause problems in blood coagulation. Any of these conditions or a decrease in platelet function may result in a disease of the platelets, which is called a thrombocytopathy. Not only the variations in the count, but dysfunctional platelets can also cause health problems.

Even though the normal platelet levels of all healthy human beings are said to be within the range of 150000 and 450000 per μl (micro liter) of blood, slight variations are considered normal in some people. According to some health experts, a value between 150000 and 450000 per μl of blood is the normal platelet count in children, whereas in adults, it can be between 150000 and 400000 per μl of blood. It has also been observed that people living in high altitudes have an increased platelet count, as compared to their counterparts. This condition can also be found in women after childbirth and those who consume oral contraceptives. Strenuous exercises may also cause a hike in the platelet count. Some women may have a low blood platelet, just before menstruation. Patients who are undergoing chemotherapy and radiation therapy may also have a low platelet count. Some rare genetic disorders like Glanzmann's Thrombasthenia, Bernard-Soulier disease and Chediak-Higashi syndrome, may also cause defective platelets.

A platelet level which is below 50,000 or above 1,000,000 is considered as critical. If the count sinks below 20,000, such a condition may cause spontaneous bleeding and is considered as life-threatening. In short, drastic variations in the normal platelet count can be considered as serious conditions, which have to be addressed as soon as possible. While these variations can be indications of diseases, serious health problems may also arise from such variations. As such, any variation in platelet count should be brought to the notice of a medical professional immediately.