Dear Doctor, My does my menstruation last almost a week yet I read that the normal period is 3 to 4 days? Am I normal? Is there something wrong with my system? Shanitah ----- Dear Shanitah, You have not specified whether this is a recent change or it has been like this since you got your first period. Normally, menstruation begins at puberty due to surge in hormones. The first few cycles, say up to six months, are irregular, but then it becomes regular. The cycle varies from individual to individual and is usually set at 21 to 30 or 35 days, minus a week. It can last from three to five to seven days. It is maintained by balance of changing hormone levels of estrogen and progesterone. Similar to puberty, around menopause, the cycles tend to become irregular. There can be scanty bleeding with a gap between cycles or there can be excess and prolonged bleeding. Menstruation stops during pregnancy and resumes again after four weeks or even up to 12 weeks after delivering a child. In some women, menstrual cycles starting after delivery may be different in duration and flow pattern from before pregnancy. Use of hormonal contraceptives can cause prolonged menstrual bleeding. It can be a side effect of anti-clotting or blood thinning drugs. Rare disorders of clotting can cause prolonged bleeding from anywhere in the body, including the vagina. Diseases affecting the uterus like endometrial hyperplasia, uterine cancer, fibroids, endometritis, uterine polyps, cervical cancer, infections, and etcetera, have prolonged bleeding as one of the major signs. Sometimes a miscarriage can occur and if a piece of the placenta is retained in the womb, it can cause prolonged vaginal bleeding with lower abdominal pain. Among non-gynaecological medical disorders, disorders of the thyroid gland liver or kidney are known to cause excess menstrual bleeding. Excess or prolonged bleeding is cumbersome. It can cause anaemia, resulting in early fatigue, breathlessness, and palpitations. It also becomes a source of pelvic infection as blood provides a rich source for microbes to grow. Due to close proximity of the bladder to the pelvic parts, pelvic infection can easily spread to the urinary bladder, causing frequency and urgency of urination which is again bothersome and needs treatment. Cause of excess/prolonged bleeding can be determined by clinical history and examination, thyroid function tests, tests for clotting and bleeding, uterine ultrasound and biopsy. Treatment depends on underlying cause. If you have a fixed cycle since menarche (beginning of menses) where bleeding occurs for seven days and flow is consistent in all cycles, there is no need to worry. It is your menstrual cycle. However, if the number of days of bleeding has increased recently or amount of bleeding has increased, it is advisable to consult a gynaecologist. Dr. Rachna Pande is a specialist in internal medicine. rachna212002@yahoo.co.uk