Key considerations:
• Most common cause: anovulatory cycles (HPO axis immaturity)
• Screen for coagulopathy in ALL adolescents with severe AUB (VWD in 20%)
• Order: CBC, PT/aPTT, VWF antigen, ristocetin co-factor

First-line treatment:
• Acute heavy: Combined OCP (35 mcg EE) every 8h → taper
• Chronic: Low-dose cyclic OCP × 3–6 months
• Avoid LNG-IUS in nulliparous adolescents initially

Red flag: If Hb <8 + coagulopathy confirmed → haematology referral

Mechanism: Chronic anovulation → unopposed oestrogen → endometrial hyperplasia

Investigations:
• LH/FSH ratio (>2:1 suggestive), testosterone, SHBG
• Pelvic USS: polycystic morphology, endometrial thickness
• If ET >7mm in reproductive age → consider biopsy

Management:
• Weight loss 5–10% → restores ovulation in 50%
• Combined OCP: first-line for cycle regulation
• Cyclic progestogen (MPA 10mg days 14–26) if OCP CI
• Metformin: if insulin resistance + anovulation
• LNG-IUS: protects endometrium long-term

Context: Erratic ovulation, declining progesterone → irregular heavy periods

Mandatory: Endometrial biopsy if age ≥45 regardless of symptoms

Investigations:
• FSH, estradiol, TSH
• Pelvic USS + ET measurement
• If ET >10mm perimenopausal → pipelle biopsy

Management options:
• LNG-IUS (Mirena): first-line — reduces bleeding by 90%
• Tranexamic acid + NSAIDs for acute episodes
• Progesterone (norethisterone 5mg tds days 5–26)
• Endometrial ablation if definitive treatment desired
• Hysterectomy if failed medical treatment

Definition: Any vaginal bleeding ≥12 months after last menstrual period

Causes:
• Endometrial cancer (10–15%)
• Endometrial atrophy (most common benign)
• Endometrial polyp, HRT related
• Cervical pathology, vaginal atrophy

Mandatory workup:
1. Pelvic USS + endometrial thickness
2. If ET ≥4mm → pipelle biopsy (mandatory)
3. If ET <4mm + single episode → observe, reassess if recurrence
4. If USS inadequate → outpatient hysteroscopy

⚠️ Do not reassure without biopsy if ET ≥4mm

Context (COEIN-I): Anticoagulation significantly worsens AUB

Key steps:
1. Do NOT stop anticoagulation without cardiology/haematology review
2. Investigate for structural cause regardless (PALM)
3. Tranexamic acid 1g TDS (evidence-based even on anticoagulation)
4. LNG-IUS: reduces bleeding by 75–80% — preferred long-term
5. If on warfarin: check TTR, consider dose adjustment

Avoid: NSAIDs (↑GI bleeding risk, platelet effect)

Immediate priorities:
1. IV access (x2 large bore cannulae)
2. Bloods: CBC, coagulation, type & screen, renal function
3. IV crystalloid → blood transfusion if Hb <7 or symptomatic

Medical haemostasis:
• Tranexamic acid 1g IV → then oral 1g TDS
• High-dose oestrogen: IV conjugated oestrogen 25mg q4–6h × 24h
• OR: Combined OCP 35mcg EE every 6h × 24h → taper

Surgical options if refractory:
• Intrauterine balloon tamponade
• Uterine artery embolisation
• Hysteroscopic resection (once stable)
• Hysterectomy (last resort)