Uterine fibroids are non-cancerous growths that develop from the muscle tissue of the uterus, affecting many women, especially during their childbearing years. While many individuals experience no symptoms, others contend with issues like heavy bleeding and pelvic pain. A less common but serious complication is urinary retention, the inability to empty the bladder completely. Depending on their size and location, fibroids can interfere with normal urinary function and cause retention.
Types of Fibroids That Affect Urinary Function
The position of a fibroid is more important than its size when determining the risk of urinary symptoms. Fibroids are categorized based on their location, and those that grow outward toward the bladder are the most likely to cause problems. Subserosal fibroids, which develop on the outer surface of the uterus, are often the primary culprits for pressure-related symptoms.
These tumors grow into the pelvic cavity and can directly press on adjacent organs like the bladder or rectum. A pedunculated fibroid is a type of subserosal fibroid that hangs from the uterine wall by a thin stalk. If these tumors grow on the anterior (front) wall of the uterus, they immediately reduce the available space for the bladder, which sits directly in front of the uterus.
Intramural fibroids, the most common type, grow within the muscular wall of the uterus. These can cause urinary issues if they grow large enough to expand the uterus significantly, increasing pressure on the surrounding anatomy. While submucosal fibroids are most associated with heavy bleeding, any fibroid that increases the overall uterine size can contribute to bladder pressure.
How Fibroid Location Causes Bladder Compression
The bladder is a flexible, muscular organ situated in the pelvis, directly in front of the uterus. As a fibroid grows, particularly an anterior subserosal mass, it encroaches upon the bladder’s space. This mechanical compression physically distorts the bladder, reducing its functional capacity to hold urine.
The continuous pressure from a large fibroid can also irritate the pelvic nerves responsible for signaling bladder fullness. This irritation may trigger the urge to urinate even when the bladder is only partially full, leading to frequent urination and urgency. The most concerning mechanism leading to retention is the physical obstruction of the urinary pathway.
When a fibroid pushes the uterus backward or causes it to become “incarcerated” in the pelvis, it can compress the proximal urethra or the bladder neck against the pubic bone. This mechanical pinching prevents the complete passage of urine, leaving residual urine in the bladder. The fibroid mass can also cause the cervix to be deflected forward, contributing to urethral compression.
The growing mass can stretch the urethra, potentially causing voiding dysfunction. In rare instances, a very large fibroid can press on the ureters, the tubes carrying urine from the kidneys to the bladder. If this pressure results in a partial or complete blockage, it can lead to hydronephrosis (swelling of the kidney due to urine backup). This anatomical distortion explains how a fibroid mass can progress from urinary frequency to the inability to void altogether.
Symptoms Associated with Fibroid-Induced Retention
Urinary retention symptoms often begin subtly and may be mistaken for common bladder issues. A common initial complaint is increased frequency of urination (polyuria), because the bladder’s capacity is physically reduced by fibroid pressure. This urge often extends into the night, causing nocturia, which disrupts sleep quality.
Individuals may also experience hesitancy (difficulty starting the urine stream) and a noticeably weak or intermittent flow. A defining symptom is the feeling of incomplete bladder emptying after voiding. This residual urine creates an environment susceptible to recurrent urinary tract infections (UTIs), further complicating the symptoms.
In the most serious scenario, a patient may experience acute urinary retention, the sudden and complete inability to pass any urine. This condition causes severe lower abdominal pain and requires immediate medical attention to drain the bladder, as it can be harmful to the kidneys. Any persistent voiding difficulty warrants a prompt medical evaluation.
Treatment Options for Pressure Relief
The treatment goal for fibroid-induced urinary retention is to reduce the size of the mass or remove the source of the pressure. Conservative management, such as monitoring, may be appropriate for mild symptoms. Medications like gonadotropin-releasing hormone agonists may be used temporarily to shrink the fibroids and ease pressure before a definitive procedure.
For definitive treatment, surgical options include a myomectomy, the surgical removal of the fibroid while preserving the uterus. Myomectomy is often the preferred option for women who wish to maintain fertility. Recovery time varies significantly depending on the technique, ranging from a few weeks for a minimally invasive approach to up to six weeks for an abdominal procedure.
A less invasive, non-surgical option is Uterine Fibroid Embolization (UFE), performed by an interventional radiologist. UFE involves injecting tiny particles into the arteries that supply blood to the fibroids, causing them to shrink over time. Because UFE is minimally invasive, it typically involves a shorter recovery time, often less than two weeks, and is considered a uterus-sparing procedure.
The complete removal of the uterus (hysterectomy) is a permanent solution that removes the possibility of fibroid recurrence. This option is generally reserved for women with severe symptoms who have completed childbearing or when other treatments have failed. The choice of treatment is individualized, depending on fibroid characteristics, symptom severity, and fertility goals.