Fibroids are remarkably common — but that doesn't mean you have to live with their symptoms. Here's everything you need to know.
Uterine fibroids are non-cancerous growths of the uterine muscle, medically known as leiomyomas or myomas. They are extraordinarily common — studies suggest that up to 70–80% of women will develop at least one fibroid by age 50, though many will never know because the fibroids cause no symptoms. When fibroids do cause symptoms, however, they can be significantly disruptive to daily life, menstrual health, and fertility.
Fibroids vary enormously in size (from a pea to a grapefruit or larger), number, and location within the uterus. Their location — whether inside the uterine cavity (submucosal), in the uterine wall (intramural), or on the outer surface (subserosal) — largely determines what symptoms they cause. Submucosal fibroids, even when small, tend to cause the most significant menstrual symptoms.
Heavy periods are the most common and often most debilitating fibroid symptom. Submucosal and intramural fibroids distort or increase the surface area of the uterine lining, leading to much heavier blood loss than normal. Women with fibroids may soak through pads or tampons every hour or two, pass large clots, and experience periods that last more than 7 days. This heavy bleeding frequently leads to iron-deficiency anemia — with fatigue, weakness, and shortness of breath — which can be as impairing as the bleeding itself. If you're experiencing significantly heavy periods, fibroids are one of the first things your doctor will look for.
Larger fibroids — particularly intramural and subserosal types — can create a persistent sensation of pelvic heaviness, pressure, or fullness, similar to the feeling of a full bladder or the second trimester of pregnancy. This pressure is caused by the physical bulk of the fibroid pressing on surrounding tissues and organs. Women sometimes describe feeling "full" in the lower abdomen even when they haven't eaten much. The pressure can worsen during menstruation when the uterus is more engorged, and may also cause visible abdominal protrusion when fibroids are large.
The bladder sits directly in front of the uterus. Fibroids — particularly those on the front of the uterus (anterior subserosal fibroids) — can press on the bladder, reducing its capacity and creating a constant urge to urinate. Some women find they need to urinate every hour or two during the day, and are woken repeatedly at night. In some cases, fibroids can cause urinary retention (difficulty fully emptying the bladder), which increases the risk of urinary tract infections. Urinary frequency caused by fibroids typically improves once the fibroids are treated or after menopause, when fibroids tend to shrink.
Fibroids can cause chronic or cyclical pelvic pain and lower back pain. During menstruation, the uterine contractions that expel the lining must work harder when fibroids are present, resulting in more intense cramping. Large fibroids can also press on pelvic nerves, causing radiating pain into the hips, buttocks, and down the legs. In rare cases, a pedunculated fibroid (one attached by a stalk) can twist, cutting off its blood supply and causing sudden, severe pain — a situation called fibroid torsion that requires immediate medical attention.
Pain during sex (dyspareunia) can occur with fibroids, particularly submucosal fibroids that distort the uterine cavity or large fibroids that change the position or angle of the uterus. Deep penetration may be uncomfortable or painful because the uterus doesn't move freely or because the fibroid itself is being compressed. Some positions may be more comfortable than others. If painful sex is new or has gotten progressively worse, it's important to mention it to your doctor — it can help differentiate fibroid-related pain from other causes like endometriosis, pelvic floor tension, or ovarian cysts.
Very large fibroids, or multiple fibroids together, can enlarge the uterus dramatically — in some cases to the size of a 5- or 6-month pregnancy. This can cause visible abdominal enlargement that's easy to mistake for weight gain. Women sometimes notice their pants fitting tighter at the waist or their abdomen feeling firm rather than soft. A uterus enlarged by fibroids can sometimes be felt on abdominal examination, and the distinction between abdominal enlargement from fibroids versus other causes (obesity, ascites, ovarian masses) is made by ultrasound. If your abdomen has become noticeably larger without explanation, it's worth investigating.
The rectum lies directly behind the uterus. Large fibroids — particularly posterior subserosal fibroids (on the back of the uterus) — can press on the rectum and cause constipation, difficulty with bowel movements, or a feeling of incomplete evacuation. This pressure can also cause rectal pain or the feeling of needing to have a bowel movement when you don't. While constipation has many causes, the combination of pelvic pressure, heavy periods, and constipation in the same woman raises strong suspicion for fibroids. Dietary measures for constipation (fiber, hydration, movement) may help symptomatically but won't address the underlying fibroid.
Beyond heavy bleeding, fibroids can cause periods that last longer than usual (more than 7 days), spotting between periods, and irregular cycle timing. Submucosal fibroids in particular disrupt the normal hormonal feedback and uterine lining shedding mechanisms. Some women experience near-continuous light bleeding or spotting, which is both physically draining and emotionally exhausting. Irregular or prolonged bleeding should always be evaluated because — while fibroids are a common cause — other conditions including endometrial polyps, adenomyosis, and rarely endometrial cancer can cause similar patterns.
Treatment decisions depend on the severity of symptoms, fibroid size and location, whether you want to preserve fertility, and how close you are to menopause (after which fibroids typically shrink). Options range from monitoring to non-invasive procedures to surgery.
For women with no or minimal symptoms, watchful waiting (periodic monitoring with ultrasound) is a reasonable approach. Many fibroids never cause problems, and all fibroids naturally shrink after menopause when estrogen levels fall.
Hormonal medications can manage symptoms but don't permanently eliminate fibroids. Options include: GnRH agonists (like Lupron) that temporarily create a menopausal state and can shrink fibroids significantly — used to reduce fibroid size before surgery or for short-term symptom management; the newer GnRH antagonists (Oriahnn, Myfembree) taken as daily pills with fewer side effects than injections; hormonal IUDs to manage heavy bleeding; and progestin-only pills or tranexamic acid to reduce menstrual blood loss.
Uterine fibroid embolization (UFE) is a minimally invasive procedure that cuts off blood supply to fibroids, causing them to shrink. It preserves the uterus and has a shorter recovery than surgery. MRI-guided focused ultrasound (MRgFUS) uses high-frequency ultrasound waves to destroy fibroid tissue non-invasively. Both are good options for women who want to avoid surgery and aren't planning future pregnancies.
Myomectomy (surgical removal of fibroids while preserving the uterus) is preferred for women who want to maintain fertility. It can be performed hysteroscopically (through the vagina for submucosal fibroids), laparoscopically, or through open abdominal surgery depending on fibroid size and location. Hysterectomy (removal of the uterus) is the only definitive cure for fibroids and eliminates recurrence entirely — it's the most commonly performed treatment for symptomatic fibroids in women who have completed childbearing.
Log your period flow, pain levels, and symptoms over time — and build the record you need to advocate for better care.
Start Tracking Free →No — uterine fibroids (leiomyomas) are benign (non-cancerous) tumors. They do not turn into cancer. There is an extremely rare form of uterine cancer called leiomyosarcoma that originates from smooth muscle cells, but it is a completely separate condition from fibroids and does not arise from existing fibroids. The risk of any uterine mass being leiomyosarcoma is very low — estimated at less than 1 in 1,000 cases. If you're concerned about any uterine mass, an ultrasound and possibly MRI can provide reassurance, and any tissue removed during fibroid surgery is sent to a lab for evaluation as a standard precaution.
It depends on their size and location. Most fibroids don't affect fertility. However, submucosal fibroids (inside the uterine cavity) and large intramural fibroids can interfere with implantation, distort the uterine cavity, or obstruct the fallopian tubes — all of which can reduce fertility or increase miscarriage risk. If you're having difficulty conceiving and fibroids have been found, a fertility specialist or reproductive surgeon can assess whether the fibroids are likely to be contributing and whether removing them would help. Myomectomy has been shown to improve pregnancy outcomes in women with submucosal fibroids in particular.
Fibroids are estrogen-sensitive and naturally shrink after menopause when estrogen levels decline. In the years before menopause, fibroids often grow slowly (though they can also remain stable or occasionally shrink on their own). Some lifestyle factors — maintaining a healthy weight, reducing alcohol, and ensuring adequate vitamin D — may modestly reduce fibroid growth risk, but there is no proven natural treatment that reliably shrinks existing fibroids to a clinically significant degree. Green tea extract (EGCG) and berberine have shown some promise in small studies, but evidence is insufficient to recommend them as treatments. For significant symptom relief, medical or procedural treatment is usually necessary.
Most fibroids are detected on pelvic ultrasound — either transabdominal (over the belly) or transvaginal (with an internal probe, which provides better detail). Ultrasound can identify the number, size, and location of fibroids. If more detail is needed — especially before surgery or to assess whether a mass might be something other than a fibroid — MRI provides much clearer tissue characterization. A saline infusion sonogram (SIS) or hysteroscopy may be used specifically to evaluate the inside of the uterine cavity for submucosal fibroids. Blood tests check for anemia from heavy bleeding.
Generally, no. Asymptomatic fibroids found incidentally on imaging or pelvic exam don't require treatment. The standard of care is watchful waiting with periodic monitoring to track size and catch any new symptoms early. There's no evidence that treating asymptomatic fibroids prevents future complications. The decision to treat should be based on symptoms and their impact on your quality of life — not fibroid size alone. Exceptions include cases where fibroids are growing rapidly (which warrants evaluation), where they're causing silent complications like ureteral obstruction, or where pretreatment is planned before fertility treatment.