Regular menstruation (period) occurs every 24-38 days, lasts for up to 8 days without any bleeding in between cycles. Abnormal uterine bleeding (AUB) is a term which refers to deviation from a regular menstruation.
You can have abnormalities in frequency. You can be bleeding too often (i.e. having a period less than 24 days apart) or too infrequent (i.e. having a period more than 38 days apart). You can have amenorrhea, which is when you do not get a period at all. Primary amenorrhea describes a condition where a woman never gets a period after the time she was supposed to start puberty. Secondary amenorrhea describes a condition where a woman was previously having a regular period for at least six months but then stops. Some women may also experience intermenstrual bleeding (i.e. bleeding in between periods).
You can have abnormalities in quantity. You can be bleeding too heavy (i.e. bleeding more than 1 pad an hour for a minimum of 2 hours straight). Heavy menstrual bleeding may lead to other issues such as anemia. You can also have very light bleeding (i.e. only spotting). Typically having a light period is not an issue unless it is an indication of cervical stenosis or scaring in the uterus.
There can be many reasons why a woman can experience abnormal uterine bleeding and it can occur in any stage of life, however; some causes of abnormal bleeding are more common in a particular season of life. Abnormal uterine bleeding can have structural causes such as fibroids, endometrial polyps, adenomyosis, or neoplasia. There can also be non structural causes to abnormal uterine bleeding such as ovulatory dysfunction, infections, disorders in blood clotting, and medications. You may need a physical exam, laboratory testing, imaging (i.e. ultrasound), and possibly a biopsy of your uterus to determine the cause of your abnormal bleeding. If you are experiencing abnormal uterine bleeding we recommend that you follow up with your provider for evaluation.