if you are using some type of hormonal birth control this might represent prolonged break through bleeding. erratic bleeding on birth control can be started if one gets an infection such as chlamydia (e. g. from new sexual partner or a partner with other partners). if you are not using hormonal birth control then the most common reason for erratic and prolonged bleeding (once an accidental pregnancy has be ruled out) is a hormonal change. usually this change is linked to a missed ovulation in the month or months before the abnormal bleed. 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 parents or boyfriends/girlfriends exams) increased body weight anorexia rotating shifts at work etc.
what could be causing my irregular periods and spotting?