II. Epidemiology
- Most common, typically benign, solid pelvic tumor in women
- More common in non-white women
III. Risk factors: Positive (increased risk of fibroids)
- Overweight women (increased Body Mass Index)
- Advancing age (until Menopause)
- Rare before Puberty
- Age 20-30 years: 4% fibroid Prevalence
- Age 30-40 years: Up to 18% fibroid Prevalence
- Age 40-60 years: 33% fibroid Prevalence
- Menopause to Lifetime: up to 70-80% Prevalence
- Regress after Menopause
- Hyperestrogenic states or EstrogenAgonist use
- Enlarge in pregnancy (and regress after Menopause)
- Black women with higher Incidence
- Larger fibroids and earlier onset
- More symptomatic fibroids (including Anemia)
- Comorbid Hypertension
- Family History of Uterine Fibroids
- Nulliparity
- Increased time interval from last birth
- Early Menarche (age <10 years old)
IV. Risk Factors: Negative (lower risk of fibroids)
- Five pregnancies or more
- Late Menarche (age >16 years old)
- Menopause (fibroids typically regress)
- Oral Contraceptive or Depo Provera use
- Tobacco Abuse
V. Pathophysiology
- Benign tumors arising from uterine, myometrial Smooth Muscle
- Malignant Leiomyosarcoma is uncommon (0.23%)
- Hormonally mediated
- Enlarge with Estrogen and Growth Hormone
- Regress with Progesterone
- Types of leiomyoma
- Pedunculated leiomyoma (FIGO 0)
- Submucosal leiomyoma (FIGO 1-2)
- Project into uterine cavity
- Associated with Abnormal Uterine Bleeding
- Intramural leiomyoma (FIGO 3-4)
- Limited to within the myometrium
- Subserosal leiomyoma (FIGO 5-6)
- Project outside Uterus
- Associated with bulk symptoms
VI. Symptoms
- Symptomatic in 20-50% of fibroid disease
- Clinically Significant requiring management in 25%
-
Abnormal Uterine Bleeding or Menorrhagia (prolonged or heavy menstrual flow, most common)
- Fibroids are most common cause of Menorrhagia
- Pelvic pressure or Pain Sensation (large fibroids, bulk effects)
- Pelvic discomfort or Low Back Pain
- Dyspareunia
- Urine symptoms (urine frequency, urine urgency, urine retention)
- Constipation
- Exacerbated by pregnancy (see below)
- Pregnancy complications
- Mixed study results, but at least one large study demonstrates increased complication risk
- Recurrent Miscarriage
- Premature labor
- Fetal Malpresentation
- Labor complications including cesarean delivery
- Placental Abruption
- Stout (2010) Obstet Gynecol 116(5): 1056-63 [PubMed]
- Controversial - relationship to fibroids not supported by evidence
VII. Signs
- Abdominal exam
- Uterus palpable above Symphysis Pubis
- Bimanual examination
- Enlarged, mobile and irregular uterine contour
VIII. Differential Diagnosis: Abnormal Uterine Bleeding
- See Abnormal Uterine Bleeding
- Structural Causes
- Adenomyoma or Adenomyosis
- Endometrial Polyp
- Endometrial Hyperplasia or Endometrial Cancer
- Non-Structural Causes
- Pregnancy (Ectopic Pregnancy, Intrauterine Pregnancy)
- Endometriosis
- Coagulopathy (e.g. Von Willebrand Disease)
- Ovulatory Dysfunction (e.g. PCOS, Thyroid disease)
- Medications (e.g. Oral Contraceptives, IUD, Tamoxifen)
IX. Differential Diagnosis: Bulk Symptoms or Pelvic Pain
X. Differential Diagnosis: Pelvic Mass
- Endometrial Cancer
- Ovarian Mass
- Pregnancy
- Malignant Leiomyosarcoma
- See Leiomyosarcoma
- May represent up to 0.23% of Uterine Fibroids
- Identified in 13 of every 10,000 women undergoing surgery for preseumed fibroids
- Risks
- Age over 45 years old (OR 20)
- Post-Menopause (OR 9.7)
- History of pelvic radiation
- Tamoxifen use
- Genetic Syndromes (hereditary Retinoblastoma, Li-Fraumeni Syndrome)
- MRI Findings
- Intramural Hemorrhage (OR 21)
- Endometrial thickening (OR 11)
- T2-Weighted signal heterogeneity (OR 10)
- Non-myometrial origin (OR 4.9)
- References
XI. Labs (If Indicated)
- Pregnancy Test
- Complete Blood Count
- Thyroid Stimulating Hormone (TSH)
- Urinalysis
- Serum 25-Hyroxyvitamin D Level
XII. Imaging
-
Transvaginal Ultrasound with doppler
- Best initial test due to cost efficacy
- Identifies fibroid size, location and number
- Least Test Sensitivity and Specificity (misses small fibroids)
- Pelvic MRI with contrast
- Best for fibroid mapping preoperatively
- Demonstrates fibroid extent, location and vascularity
- Expensive
XIII. Diagnostics
-
Endometrial Biopsy
- Indicated in Abnormal Uterine Bleeding with risk factors for Endometrial Hyperplasia or cancer
- Indications
- See Abnormal Uterine Bleeding
- Women age >35-45 years
- Unopposed Estrogen
- Polycystic Ovary Syndrome
- Persistent Abnormal Uterine Bleeding despite treatment
- Saline Infusion Sonohysterography or hysteroscopy
- Good Test Sensitivity and Specificity, but invasive
XIV. Management: Surgery
-
Hysterectomy
- Fibroids account for up to 33-39% of hysterectomies
- Indications
- Postmenopausal women with enlarging fibroids
- Peristent Abnormal Uterine Bleeding
- Symptomatic fibroids refractory to other measures
- Myomectomy
- Performed with hysteroscopy, laparoscopy, robotic-assisted or laparotomy
- Excision of fibroids with preservation of Uterus
- High risk of recurrence (15-30% in 5 years)
- Up to 10% of women will subsequently undergo Hysterectomy within 5-10 years
- Indications (typically in women who want to preserve fertility)
- Submucosal Fibroids <3 cm (and >50% tumor is intracavitary)
- Uterine Fibroid Embolization
- Uterine arteries occluded with polyvinyl Alcohol foam (or other embolic agents)
- Incomplete embolization used now to reduce pain
- Intervention Radiology procedure under IV sedation
- Well tolerated (less painful than surgery)
- Post-embolization syndrome (low grade fever, pain and passing of fibroid tissue vaginally) is common
- Second procedure required in 20-33% of cases within 5 years
- References
- Uterine arteries occluded with polyvinyl Alcohol foam (or other embolic agents)
- Myolysis
- Fibroid destruction by coagulation necrosis (Nd-YAG laser, bipolar needle or MR-guided focused Ultrasound)
- Often combined with endometrial ablation
- Recurrence rate not yet established
- Indications
- Fibroids in women who want to preserve fertility
XV. Management: Medical
- Observation (preferred for asymptomatic cases)
- Most fibroids decrease in size with Menopause
- Agents effective in Menorrhagia but are not typically effective at reducing fibroid size
- Often used as first-line measures due to lower adverse effects
- Levonorgestrel IUD (Mirena IUD)
- More effective in reducing uterine bleeding than Oral Contraceptives
- Sayed (2011) Int J Gynaecol Obstet 112(2): 126-30 [PubMed]
- Progestins (e.g. Depo Provera)
- Oral Contraceptive cycling
- Minimally effective (much less effective than Mirena IUD)
- NSAIDs
- Reduce blood loss and pain
- Tranexamic Acid (Lysteda, Cyklokapron)
- Take two 650 mg tabs (1.3 g) orally three times daily for up to the first 5 days of the Menstrual Cycle
- Avoid combining with Estrogen containing products (increased thrombosis risk)
- Peitsidis (2014) World J Clin Cases 2(12): 893-8 [PubMed]
- Other agents
- Androgenic agents (e.g. Danazol)
-
GnRH Antagonists
- Indicated in Fibroid related Menorrhagia, refractory to other measures above
- Limit to no more than 2 years of use
- GnRH Antagonists lower Estradiol and Progesterone levels (menopausal levels)
- Reduce Menstrual Bleeding
- Increases bone loss, Hot Flashes (hence add back therapy as below)
- Does not provide Contraception and should not be used with Hormonal Contraception
- Combination Agents with add-back Hormones ($1000/month in 2022)
- Relugolix/Estradiol/Norethindrone (Myfembree) once daily
- Elagolix/Estradiol/Norethindrone (Oriahnn) twice daily
- References
- (2022) Presc Lett 29(2): 10-1
-
GnRH Agonists (induce hypoestrogenism)
- Indicated in perimenopausal women, or preoperatively to reduce size
- Limit to short term use (e.g. bridging to Hysterectomy)
- Decreases Estrogen and Progesterone via negaive feedback
- Results in Amenorrhea and fibroid mass reduction
- Fibroids recur when medication stopped
- Hypoestrogenic side effects (Hot Flushes, BMD risk)
- Injectable GnRH Agonists include Leuprolide, Goserelin, Triptorelin
- Used in combination with Progesterone
- Reduces Hot Flushes (vasomotor symptoms)
- Lethaby (2002) BJOG 109(10): 1097-108 [PubMed]
- Selective Progesterone receptor modulators (SPRM)
- Background
- Improves Abnormal Uterine Bleeding and uterine enlargement
- Not FDA approved for fibroid use due to safety concerns
- Mifepristone (Mifepex) 5 mg daily
- Ulipristal (Ella)
- Risk of severe liver injury (requiring Liver Transplant in some cases)
- Carbonell Esteve (2008) Obstet Gynecol 112(5): 1029-36 +PMID:18978102 [PubMed]
- Background
- Complimentary and Alternative Therapy
- Other measures not found consistently effective
XVI. Management: Emergent Heavy Bleeding
- See Emergent Management of Acute Heavy Uterine Bleeding
- ABC Management
- Two large bore IVs (e.g. 18 gauge)
- Emergent consult to Gynecology
- Labs
- Complete Blood Count with Platelet Count
- Type and Cross
- Coagulation studies (e.g. INR, PTT)
XVII. References
- Stewart (2012) Mayo POIM Conference, Rochester
- De La Cruz (2017) Am Fam Physician 95(2): 100-7 [PubMed]
- Evans (2007) Am Fam Physician 75:1503-8 [PubMed]
- Keating (2025) Am Fam Physician 112(4): 393-400 [PubMed]
- Myers (2002) Obstet Gynecol 100:8-17 [PubMed]
- Rackow (2006) Gynecol Clin North Am 33:97-113 [PubMed]
- Vilos (2015) J Obstet Gynaecol Can 37(2): 157-81 [PubMed]