Uterine fibroids are common, non-cancerous growths that develop in or on the uterus. While many individuals with fibroids experience no symptoms, abnormal bleeding stands out as one of their most frequent and impactful manifestations. This bleeding can significantly affect a person’s quality of life. Understanding the biological reasons behind this bleeding is important for those affected.
Understanding Uterine Fibroids
Uterine fibroids, also known as leiomyomas, are benign growths of muscle and fibrous tissue. They vary in size, from a seed to masses that distort the uterus. Their location within the uterus is a key factor influencing symptoms.
There are three primary types based on position. Intramural fibroids are the most common, growing within the muscular wall. Subserosal fibroids develop on the outer surface, sometimes extending into the pelvis. Submucosal fibroids grow just beneath the inner lining, protruding into the uterine cavity. Submucosal fibroids are particularly associated with abnormal bleeding, even when small.
Mechanisms Behind Fibroid Bleeding
Several mechanisms contribute to abnormal bleeding. The location of a fibroid, especially its proximity to the uterine lining, plays a significant role. Submucosal fibroids, for instance, can directly disrupt the endometrium, the tissue that sheds during menstruation. This disruption leads to irregular or heavy bleeding as the lining is not uniformly supported.
Fibroids can also increase the total surface area of the uterine lining. As they grow, they may enlarge the uterine cavity, meaning more endometrial tissue sheds during each menstrual cycle. This results in greater blood loss. Fibroids can also cause new, fragile blood vessels to develop within the uterine wall and endometrium. These vessels are prone to rupture, increasing bleeding.
Hormonal influences also play a part, as fibroids are sensitive to estrogen and progesterone. Fluctuations in these hormones, in conjunction with the presence of fibroids, can lead to imbalances in the growth and shedding of the uterine lining. This hormonal interplay can contribute to prolonged or heavy bleeding episodes. Fibroids can also interfere with the uterus’s natural ability to contract effectively. After menstruation, the uterus typically contracts to compress blood vessels and reduce blood flow, but larger or multiple fibroids can impede this process, leading to extended bleeding. Localized inflammatory responses or the release of specific growth factors by fibroids can also contribute to abnormal bleeding patterns.
Recognizing Fibroid-Related Bleeding Patterns
Abnormal bleeding associated with fibroids presents in several patterns. Heavy menstrual bleeding, medically termed menorrhagia, is a common symptom. This involves soaking through one or more sanitary products hourly for several consecutive hours, or passing large blood clots. Menorrhagia often necessitates frequent sanitary product changes and can disrupt daily activities.
Periods that last significantly longer than the typical seven days are also characteristic of fibroid-related bleeding. This prolonged flow can be continuous or intermittent throughout the extended duration. Bleeding or spotting between periods, known as intermenstrual bleeding or metrorrhagia, is another pattern that may occur with fibroids. This occurs outside the regular menstrual cycle.
Chronic heavy blood loss from fibroids can lead to anemia. Anemia occurs when there are insufficient red blood cells to carry oxygen. Individuals might experience fatigue, weakness, dizziness, or shortness of breath.
When to Seek Medical Advice
Individuals experiencing abnormal bleeding should consult a healthcare professional. Extremely heavy bleeding, such as soaking multiple sanitary pads or tampons hourly for several hours, warrants prompt medical attention. This can quickly lead to significant blood loss.
Bleeding lasting considerably longer than a typical period, or occurring between periods, should also be evaluated. If menstrual bleeding consistently interferes with daily activities, causes significant pain, or indicates anemia, medical advice is appropriate. Any new or worsening changes in menstrual patterns, particularly a sudden increase in severity or frequency, should prompt a consultation.