For menstruating adolescents, an average menstrual cycle lasts 28 days - starting with the first day of the last period (which, on average, lasts six days, with some girls having a very light flow and others having a very heavy flow) and ending with the first day of the next menstrual period. However, the length of the cycles varies, particularly for the first one to two years after menarche (a young woman's first menstrual period). Young women may have cycles as short as 23 days, or as long as 35 days. However, anything that deviates from this range is considered abnormal and may require medical attention.
North Shore-LIJ gynecologists are experienced in the diagnosis and treatment of abnormal menstrual bleeding. For more information on abnormal bleeding or to schedule a consultation, please contact the Division of Pediatric and Adolescent Gynecology at Cohen Children’s Medical Center of New York at 516-390-9258. For an emergency call 911 or go to the Cohen Children's Medical Center Emergency Room.