Residency · Residency · Interventional Radiology
Uterine Fibroid Embolization
Overview
Uterine fibroid embolization (UFE), also termed uterine artery embolization (UAE), is a minimally invasive treatment for symptomatic uterine leiomyomas. Bilateral uterine artery embolization causes ischemic infarction of fibroids while preserving the uterus. First described by Ravina et al. in 1995; now a well-established alternative to hysterectomy and myomectomy. Performed by interventional radiologists; typically requires overnight admission for pain management.
Indications and Patient Selection
Symptoms Amenable to UFE
Menorrhagia (heavy menstrual bleeding) — most common indication. Bulk-related symptoms: pelvic pressure, urinary frequency, constipation. Dysmenorrhea and pelvic pain. Iron deficiency anemia secondary to menorrhagia.
Ideal Candidates
Premenopausal women with symptomatic fibroids. Patients desiring uterine preservation but not necessarily fertility. Patients who are poor surgical candidates or prefer minimally invasive approach. Multiple fibroids (UFE treats all fibroids simultaneously, unlike myomectomy).
Relative Contraindications
Active pregnancy. Active pelvic infection or endometritis. Suspected uterine malignancy (leiomyosarcoma) — MRI screening important. Pedunculated subserosal fibroids with narrow stalk (risk of detachment and torsion). Desire for future fertility (controversial — see below). Postmenopausal patients (fibroids typically regress). Very large uteri (>24-week size) — increased complication risk, may still be treated.
Pre-Procedural Workup
Pelvic MRI with contrast: gold standard for fibroid mapping, subtype classification, and sarcoma screening. Endometrial biopsy if abnormal bleeding pattern or endometrial thickening. Complete blood count (anemia assessment). Basic metabolic panel, coagulation studies. Pregnancy test. Gynecology consultation and shared decision-making.
<image>Pelvic MRI (T2-weighted) showing multiple intramural and submucosal uterine fibroids of varying sizes with characteristic low signal intensity</image>
Anatomy and Technique
Uterine Artery Anatomy
Uterine artery arises from the anterior division of the internal iliac artery. Crosses the ureter ("water under the bridge") at the level of the cervix. Ascends along the lateral uterine wall within the broad ligament. Gives off arcuate arteries that penetrate the myometrium. Fibroids are supplied predominantly by uterine arteries; collateral supply from ovarian arteries in ~10%.
Access and Catheterization
Unilateral common femoral artery access (right CFA most common) — single-puncture technique. Alternatively: bilateral femoral access or radial access. 5-Fr sheath; Waltman loop or Roberts uterine catheter for contralateral uterine artery. 4-Fr or 5-Fr Cobra or reverse-curve catheter for ipsilateral uterine artery. Microcatheter (2.4–2.8 Fr) advanced into the horizontal segment of each uterine artery. Position catheter tip distal to the cervicovaginal branch to avoid non-target embolization.
Embolic Agents
| Agent | Type | Size Range | Key Feature | Usage |
|---|---|---|---|---|
| Embosphere (tris-acryl gelatin) | Calibrated microsphere | 500-700, 700-900 µm | Most published data, predictable | First-line |
| BeadBlock | Calibrated microsphere | 500-700, 700-900 µm | PVA-based, compressible | Alternative |
| PVA particles | Irregular particles | 355-500, 500-710 µm | Less uniform penetration | Largely replaced |
| Gelfoam | Absorbable gelatin | Variable | Temporary occlusion, recanalization risk | Not recommended as primary |
Calibrated microspheres (Embosphere, BeadBlock): most commonly used. 500–700 µm and 700–900 µm size ranges most common. Achieve consistent distal penetration into perifibroid plexus. Tris-acryl gelatin microspheres (Embosphere): most published data. PVA particles: less uniform, still used but largely replaced by calibrated spheres. Gelfoam: not recommended as primary agent (too proximal occlusion, allows recanalization).
Embolization Endpoint
Inject slowly under fluoroscopic guidance until near-stasis in the uterine artery. "Pruned tree" appearance: loss of normal arterial branches with stasis of contrast. Avoid reflux into the internal iliac artery (non-target embolization risk). Bilateral embolization is essential — unilateral treatment has higher failure rates. If ovarian artery collateral supply is identified, it may be embolized (controversial — fertility implications).
<image>Selective uterine arteriogram showing hypervascular fibroid blush before embolization (left) and near-stasis with pruned-tree appearance after embolization (right)</image>
Post-Procedural Management
Post-Embolization Syndrome
Expected in nearly all patients: pelvic pain, cramping, nausea, low-grade fever, malaise. Typically peaks at 6–12 hours, resolves over 7–10 days. Pain management: PCA (patient-controlled analgesia) with morphine or hydromorphone overnight. Ketorolac, acetaminophen, and antiemetics as adjuncts. Most patients discharged within 24 hours; some centers perform as same-day procedures.
Recovery Timeline
Return to normal activity: 1–2 weeks (vs. 4–6 weeks for hysterectomy). Menstrual cycle: expect first period may be heavier or irregular, then progressive improvement. Symptom improvement typically evident by 3 months. Fibroid volume reduction occurs over 3–12 months.
Outcomes
Symptom Control
Menorrhagia improvement: 85–95% of patients. Bulk symptom improvement: 80–90%. Overall patient satisfaction: 85–93%. Symptom recurrence/reintervention rate: 15–25% at 5 years.
Fibroid Volume Reduction
Average fibroid volume reduction: 40–60% at 6–12 months. Uterine volume reduction: 30–50%. Larger fibroids may have greater absolute shrinkage but smaller percentage reduction. Non-enhancing fibroids on follow-up MRI indicate successful infarction.
Comparison with Surgical Options
vs. Hysterectomy: UFE has shorter recovery, less blood loss, preserves uterus; hysterectomy is definitive (no recurrence). EMMY trial: UFE equivalent to hysterectomy for quality of life at 5 years; ~28% UFE patients required secondary intervention. REST trial: similar satisfaction but higher reintervention after UFE. vs. Myomectomy: UFE treats all fibroids simultaneously; myomectomy better for fertility preservation in women desiring pregnancy. vs. MRI-guided focused ultrasound (MRgFUS): UFE has broader applicability; MRgFUS limited by fibroid number, size, and location.
Fertility Considerations
The effect of UFE on fertility remains the most significant controversy. Several case series report successful pregnancies after UFE. Potential concerns: Diminished ovarian reserve (especially in women >40, from non-target ovarian artery embolization). Increased risk of miscarriage, preterm delivery, malpresentation, and cesarean section in some series. Placental abnormalities theoretically possible from endometrial ischemia. Current consensus: myomectomy remains preferred for women actively planning pregnancy. UFE may be considered for fertility in patients who are poor surgical candidates or have failed myomectomy. Counsel patients thoroughly about reproductive implications.
<image>Follow-up pelvic MRI at 6 months post-UFE showing significant reduction in fibroid volume with loss of internal enhancement indicating successful infarction</image>
Complications
Common (Expected)
Post-embolization syndrome (>90%). Vaginal discharge (fibroid expulsion fragments). Transient amenorrhea (especially in women >45).
Uncommon
Fibroid expulsion/transcervical passage (5–10%) — can be painful, may require gynecologic management. Persistent amenorrhea/premature ovarian failure (1–3%, higher in women >45). Endometritis/pyomyoma (1–2%). Non-target embolization (ovary, bladder, bowel). Uterine necrosis (rare, <1%). Access site complications (hematoma, pseudoaneurysm).
Rare / Serious
Sepsis from infected necrotic fibroid (very rare, requires emergent hysterectomy). Pulmonary embolism. Death (<0.1%).
Clinical Pearls
MRI is essential pre-procedure: it differentiates fibroids from adenomyosis (which responds less well) and screens for features suspicious for leiomyosarcoma (rapid growth, high T2 signal, central necrosis in premenopausal patient). Position the microcatheter distal to the cervicovaginal branch — non-target embolization can cause cervical necrosis. Bilateral embolization is mandatory; unilateral treatment leads to collateral reconstitution and treatment failure. Women over 45 have a significantly higher risk of permanent amenorrhea post-UFE — counsel accordingly. Pedunculated subserosal fibroids with a stalk narrower than 50% of the fibroid diameter should not be embolized (torsion risk). Submucosal fibroids may be expelled vaginally after UFE — this is generally a favorable outcome but can present with pain and discharge. Post-procedural pain is the most challenging aspect of UFE — an aggressive multimodal pain management protocol is essential for patient satisfaction. If a patient has a dominant submucosal fibroid with heavy bleeding, hysteroscopic myomectomy may be a better first-line option than UFE.
References
- Ravina JH, et al. Arterial Embolisation to Treat Uterine Myomata. Lancet. 1995;346(8976):671-672.
- de Bruijn AM, et al. Uterine Artery Embolization vs Hysterectomy in the Treatment of Symptomatic Uterine Fibroids: 10-Year Outcomes from the EMMY Trial. Am J Obstet Gynecol. 2016;215(6):745.e1-745.e12.
- Moss JG, et al. Randomised Comparison of Uterine Artery Embolisation (UAE) with Surgical Treatment in Patients with Symptomatic Uterine Fibroids (REST Trial). BMJ. 2011;343:d4547.
- Spies JB, et al. Uterine Artery Embolization for Leiomyomata. Obstet Gynecol. 2004;104(1):75-83.
- Homer H, Saridogan E. Uterine Artery Embolization for Fibroids Is Associated with an Increased Risk of Miscarriage. Fertil Steril. 2010;94(1):324-330.
- Duvnjak S, et al. ACR/SIR Practice Parameter for Uterine Artery Embolization. J Vasc Interv Radiol. 2020;31(1):1-8.
