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]