Hello, A few probable causes of irregular periods are having an intrauterine device (IUD), changing birth control pills or using certain medications, too much exercise, Polycystic ovary syndrome (PCOS), pregnancy or breastfeeding, overactive thyroid (hyperthyroidism) or underactive thyroid (hypothyroidism), thickening of or polyps on the uterine lining, or uterine fibroids. A less common cause is severe scarring (adhesions) of the lining of the uterus, a condition that doctors call Asherman syndrome. Always treatment depends upon the underlying cause. You may consult a gynecologist for a specific diagnosis and appropriate treatment. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Pallavi M., Anesthesiologist