Polycythemia can result from internal problems with the production of red blood cells. This is termed primary polycythemia. If polycythemia is caused due to another underlying medical problem, it is referred to as secondary polycythemia.
PMS can last 1-2 weeks. Premenstrual syndrome (PMS) is characterized by a number of symptoms related to a womanâs menstrual cycle. They occur a week or two before monthly menstruation begins, and ordinarily, they disappear at that time.
The average menstrual cycle lasts about 28 days, but can last anywhere from 24 to 42 days. There are three major phases of the menstrual cycle: the menstrual phase, the proliferate phase, and the secretory phase. Click here for more information on menstrual products.