Heavy menstrual bleeding can cause you to change your tampon or pad every hour or two, or wear a tampon and pad together. And heavy periods aren’t just a nuisance. In some cases, they lead to anemia—an abnormally low amount of red blood cells. Anemia can make you weak, dizzy, and short of breath. There are many causes of heavy menstrual bleeding. This includes reproductive tract conditions and diseases outside the pelvis, such as thyroid, kidney or liver problems. Finding the correct cause can help you and your doctor pinpoint a treatment—and provide relief from heavy periods. 1. Endometriosis Endometriosis is when endometrial tissue—or lining of the uterus—grows outside the uterus. It attaches to other organs and reproductive structures, such as the ovaries and fallopian tubes. Along with heavy bleeding, endometriosis can cause infertility, pain during sex, and pain in the belly or lower back. Endometriosis is common and usually affects women between 25 and 40 years of age. 2. IUDs Intrauterine devices (IUD’s) are small, T-shaped devices inserted into the uterus to prevent pregnancy. Some IUDs have hormones, and some don’t. Non-hormonal IUDs can sometimes cause heavier periods, as well as cramps, longer or irregular bleeding, and pain during sex. If you experience any of these with an IUD, talk with your doctor about your birth control options. 3. Uterine Fibroids Uterine fibroids are noncancerous growths in muscle tissue of the uterus. Uterine fibroids can grow on the inside or the outside of the uterus. In addition to heavy menstrual bleeding, uterine fibroids can cause cramps, lower back pain, difficulty urinating, and constipation. Uterine fibroids are more common for women in their 30s. 4. Uterine Polyps Uterine polyps are ball-shaped growths in the endometrium. Uterine polyps are often benign, but they’re sometimes cancerous or precancerous. Other symptoms of uterine polyps are bleeding between periods and irregular periods. Polyps become more common as you approach menopause. 5. Hormone Imbalance An imbalance of hormones can cause the lining of the uterus to grow and be too thick. This can lead to heavy menstrual bleeding. Hormone imbalance that causes heavy bleeding is more common when girls first start getting their periods, and as women approach menopause. 6. Miscarriage or Ectopic Pregnancy If you have a notably late period that’s also heavy, it could be a sign of a miscarriage or an ectopic pregnancy. Ectopic pregnancy occurs when a fertilized eggs implants outside of the uterus. Both ectopic pregnancy and miscarriage can cause lower abdominal cramps in addition to heavy bleeding. 7. Bleeding Disorders Bleeding disorders prevent blood from clotting. Bleeding disorders that can cause heavy periods include von Willebrand disease, hemophilia, and leukemia. Bleeding disorders can lead to bleeding after an injury, surgery, or childbirth, as well as frequent nosebleeds, and excessive bruising. 8. Adenomyosis Adenomyosis is a condition in which the endometrium (the lining of the uterus) grows into muscle tissue of the uterus. In addition to heavy bleeding, other symptoms include cramps and pain during sex. Adenomyosis is more common in women in their later childbearing years who have been pregnant in the past. If your family is complete, your doctor may recommend removing your uterus. It isn’t necessary to remove your ovaries. 9. Reproductive Cancer Reproductive cancers include cancer of the uterus, cervix, endometrium, and vagina. Fortunately, cancer is a less common cause of heavy bleeding during periods. Other symptoms can include pressure or heaviness in the belly area, belly or back pain, and bloating. 10. Certain Medications Occasionally, certain medications—especially anticoagulants, such as warfarin (Coumadin) and heparin, that thin the blood—can cause heavy menstrual bleeding. Aspirin also can cause heavy bleeding. For pain relief with your menstrual period, choose non-aspirin over-the-counter pain relievers. If you experience heavy periods after beginning a new medication, talk with your doctor.