When should uterine bleeding be concerning?

When Uterine Bleeding Should Be Concerning

Uterine bleeding requires urgent medical evaluation when it saturates a large pad or tampon hourly for at least 4 hours, causes hemodynamic instability, or occurs during pregnancy. 1

Types of Concerning Uterine Bleeding

Acute Severe Bleeding

• Hemodynamic instability: Bleeding causing lightheadedness, tachycardia, hypotension
• Heavy volume: Saturating a large pad or tampon hourly for ≥4 hours 1
• Severe anemia: Requiring transfusion or causing significant symptoms

Abnormal Patterns Requiring Evaluation

1. Heavy menstrual bleeding (menorrhagia):

   • Bleeding lasting >7 days
   • Blood loss >80ml per cycle
   • Passing large clots
   • Requiring frequent pad/tampon changes (hourly)

2. Intermenstrual bleeding:

   • Bleeding between regular menstrual periods
   • Particularly concerning in women >35 years

3. Postmenopausal bleeding:

   • Any bleeding after 12 months of amenorrhea
   • Requires immediate evaluation to rule out malignancy

4. Bleeding during pregnancy:

   • Any vaginal bleeding during pregnancy requires immediate evaluation
   • May indicate placenta previa, placental abruption, or vasa previa 1

Risk Factors That Make Bleeding More Concerning

• Age >35 years with recurrent anovulatory bleeding (increased endometrial cancer risk) 1
• Obesity (increased endometrial cancer risk)
• Diabetes or PCOS (increased risk of endometrial hyperplasia)
• Family history of gynecologic cancer
• Bleeding that persists despite treatment
• Bleeding with anticoagulant use

Evaluation Algorithm for Concerning Bleeding

1. Initial assessment:

   • Pregnancy test (β-hCG)
   • Complete blood count to assess anemia
   • Coagulation studies if heavy bleeding
   • TSH and prolactin levels to rule out endocrine causes 1

2. Imaging:

   • Combined transabdominal and transvaginal ultrasound with Doppler is the most appropriate initial imaging study 1
   • If uterus is incompletely visualized, MRI of pelvis without and with contrast is appropriate 1
   • Sonohysterography if polyp is suspected 1

3. Tissue sampling:

   • Endometrial biopsy for women:
     • ≥35 years with recurrent anovulation
     • <35 years with risk factors for endometrial cancer
     • With excessive bleeding unresponsive to medical therapy 2

Management Based on Findings

For Structural Causes (PALM)

• Polyps: Polypectomy
• Adenomyosis: Hormonal treatment or surgical options
• Leiomyoma (fibroids): Size-dependent management
• Malignancy/hyperplasia: Referral to gynecologic oncologist for hyperplasia with atypia or cancer 1

For Non-structural Causes (COEIN)

• Coagulopathy: Treat underlying disorder
• Ovulatory dysfunction: Hormonal regulation
• Endometrial: Hormonal treatments
• Iatrogenic: Adjust medications
• Not yet classified: Based on findings

Common Pitfalls to Avoid

1. Delaying evaluation of postmenopausal bleeding or heavy acute bleeding
2. Performing digital pelvic examination before ruling out placenta previa in pregnant women 1
3. Failing to consider medication effects (anticoagulants, hormonal contraceptives)
4. Missing endometrial sampling in high-risk women
5. Attributing all bleeding to hormonal contraception without ruling out other pathology 3

Remember that while some bleeding patterns may be expected with hormonal contraceptive use, persistent heavy bleeding requires thorough evaluation to rule out underlying pathology, even in contraceptive users 1.