What causes breast tenderness?

Causes of Breast Tenderness

Breast tenderness is primarily caused by hormonal fluctuations, with cyclical mastalgia accounting for up to 70% of cases, while non-cyclical breast pain (25%) may result from inflammatory conditions, medications, or anatomical factors. 1, 2

Types of Breast Pain and Their Causes

Cyclical Breast Pain (70% of cases)

• Hormonal factors:
  • Normal menstrual cycle fluctuations (most common)
  • Abnormal end-organ sensitivity to normal hormone levels
  • Altered local hormone receptors
  • Disorders of lipid metabolism or fatty acid levels
• Characteristics:
  • Diffuse, bilateral or unilateral pain
  • Waxes and wanes with menstrual cycle
  • Most pronounced during luteal phase
  • Most common in women in their 30s
  • Often resolves at menopause (40% of cases)
  • 14-20% resolve spontaneously within 3 months 1, 2

Non-cyclical Breast Pain (25% of cases)

• Inflammatory causes:
  • Duct ectasia with periductal inflammation (25% of non-cyclical cases)
    • Associated with heavy smoking
    • Presents as burning pain behind nipple
  • Infection or mastitis
• Anatomical factors:
  • Large breast size (associated with neck, shoulder, and back pain)
• Medication-related:
  • Hormonal medications (HRT, oral contraceptives, fertility treatments)
  • Selective serotonin reuptake inhibitors (SSRIs)
• Characteristics:
  • Usually unilateral and more focal
  • More common in women in their 40s
  • Up to 50% resolve spontaneously 1, 2

Referred Pain (10-15% of "breast pain" cases)

• Costochondritis
• Musculoskeletal conditions
• Spinal issues
• Cardiac or pulmonary disease 2

Special Considerations

Postmenopausal Women

• Hormone replacement therapy (HRT) can cause breast tenderness
  • Oral HRT associated with higher incidence of breast tenderness (57.6%) compared to transdermal HRT (36.0%) 3
  • Paradoxically, HRT may relieve breast tenderness in women who experience it prior to treatment 4
  • Women who are older and further from menopause may be more likely to develop tenderness with HRT 4

Pregnancy

• Common and typically self-limiting
• Usually managed with conservative measures (supportive bra) 2

Red Flags Requiring Further Evaluation

• Pain associated with a palpable mass
• Persistent focal pain
• Signs of infection
• Skin changes
• Nipple discharge 2

Common Misconceptions

• No convincing scientific evidence that eliminating or reducing caffeine intake significantly affects breast pain, despite widespread belief 1
• No direct relationship between mastalgia and fibrocystic changes or total-body water retention 1
• No relationship between extent of nodularity and severity of pain 1

Clinical Implications

• Focal breast pain should not be dismissed without appropriate imaging workup 2
• Risk of malignancy is extremely low when pain is the only symptom, particularly with diffuse or cyclical patterns 2
• Some research suggests cyclical breast tenderness may be associated with increased breast cancer risk in premenopausal women, with an odds ratio of 3.32 for severe tenderness 5

Understanding the multifactorial nature of breast tenderness helps guide appropriate evaluation and management, with recognition that most cases are benign and often self-limiting.