Intramural fibroids, the most common type, grow inside the uterine wall. Subserous or subserosal fibroids grow outward from the uterine wall into the abdominal cavity. Submucous fibroids grow inward from the uterine wall, taking up space within the uterus itself This type of fibroid is the most likely to cause symptoms of heavy, prolonged menstrual bleeding. Small fibroids usually cause few if any symptoms. But, as a fibroid grows larger, it may press on the bladder and the ureters, the pair of tubes that connect the bladder to the kidneys.
Fibroids can sometimes be a cause of miscarriages and infertility.
For many women, the most distressing symptom is prolonged, heavy bleeding at the time of their menstrual periods, as well as spotty vaginal bleeding outside of the normal menstrual cycle. Women who lose too much blood may become anemic. Fibroids tend to grow in spurts, with periods of rapid growth punctuated by periods of no or very slow growth. As a woman approaches menopause, a fibroid may begin to grow rapidly. After menopause, however, fibroids stop growing and may start to shrink.