there are two major reasons for very prolonged/heavy periods: hormonal and what i call "structural". "structural" means when excessive bleeding is due to actual problems within the cavity or walls of the uterus. some examples of this would include fibroids of the uterus endometriosis of the muscular wall of the uterus ("adenomyosis") infections of the lining of the uterus (e. g. gonorrhea or chlamydia) polyps of the uterine lining or even uterine cancer (much less likely in a younger woman). hormonal causes are usually linked to missed or erratic ovulations. as you may know in a normal cycle estrogen is produced all month. estrogen is responsible for building up the lining of your uterus so you have something to shed each month. in a normal cycle progesterone production increases following ovulation. progesterone "stabilizes" the uterine lining in preparation for a possible implantation of a new pregnancy. if you are not pregnant that month the levels of estrogen and progesterone fall triggering the release of the uterine lining—your period. so if you do not ovulate the estrogen build up of the lining continues but without the usual ovulation associated progesterone. thus the hormone levels don't decline and the lining stays up inside the uterus—your missed/late period. alternatively the lining can begin to shed under its own weight producing prolonged bleeding. . causes for not ovulating are multifold: thyroid problems pituitary problems ovarian cysts physical stressors (e. g. sudden increases in exercise crash dieting) emotional stressors (problems with partners work/school finances) increased body weight anorexia rotating shifts at work etc. .
what would cause me to have my period for three months straight?