According to the Office of Women's Health, an irregular menstrual cycle is one that is less than 21 days or longer than 35 days. The first day of bleeding is day one when counting the days in your cycle, and the end day of the cycle is the first day of bleeding in your next cycle. Most women have an irregular period at some point during their lives, but it isn't always due to pregnancy. There are several factors that may cause an irregular period including age, body type, lifestyle, medications, and more. You should talk with your doctor if you think you might be pregnant because there are certain tests that can confirm this diagnosis. Your doctor will also be able to help you figure out the reason for your irregular period. Some treatments available include birth control pills, progesterone supplements, hormone therapy after menopause, and even surgery. Many women with irregular periods hope they will become pregnant eventually and will try to wait it out until they can have children. If this is the case for you, try not to worry about getting pregnant every month. It is very unlikely that you will get pregnant every month just by trying. Your doctor may ask you questions about how long your cycles are and what kind of bleeding you experience. They will also want to know if you have ever been pregnant before. Once they understand the situation, they will be able to tell you what type of treatment is right for you.