12-phase flow (12)

1. 1FRAME
   AUB is a SYMPTOM in a NONGRAVID reproductive-age woman — exclude pregnancy first; PALM-COEIN is additive (causes coexist). FIGO System 1 (pattern) is the gateway to System 2 (cause) (Munro PMID 21345435; 30198563)
   inputs: age, bleeding_pattern_figo_system1
   advance: scope confirmed: nongravid reproductive-age woman with abnormal bleeding pattern
2. 2ENTRY
   Recognise the FIGO System 1 pattern: heavy menstrual bleeding, intermenstrual, irregular/infrequent, post-coital, or incidental anaemia (Jain PMID 37538019)
   inputs: bleeding_pattern_figo_system1
   advance: entry trigger present + System 1 pattern characterised
3. 3CONTEXT
   Age (malignancy + bleeding-disorder prior), bleeding history since menarche/family/surgical (AUB-C pivot), ovulatory history (AUB-O), unopposed-oestrogen risk factors (obesity/PCOS/Lynch/tamoxifen), anticoagulant/hormonal/IUD (AUB-I), US-MEC comorbidities, reproductive intent (Munro PMID 21345435; Nguyen PMID 39106314; Comishen PMID 39617186)
   inputs: age, bleeding_since_menarche_or_family_or_surgical, ovulatory_history, unopposed_estrogen_risk_factors, anticoagulant_or_antiplatelet, us_mec_comorbidities, reproductive_intent
   actions: workup.abnormal_uterine_bleeding
   advance: PALM-COEIN risk profile + reproductive intent + US-MEC eligibility captured
4. 4RED_FLAGS
   Acute heavy AUB with haemodynamic instability (orthostasis / SBP < 90 / HR > 110 / Hb crash) → ED haemorrhage path (IV access, type & screen, IV conjugated oestrogen / high-dose COC / IV TXA / intrauterine tamponade / D&C). Pregnancy-related bleeding → ectopic/abortion pathway. Postmenopausal-pattern bleeding → expedited malignancy workup (ACOG CO 557 PMID 23635706)
   inputs: sbp, hr, beta_hcg
   actions: calc.palm_coein
   advance: instability addressed; pregnancy excluded; emergent haemostasis initiated if unstable
5. 5INITIAL_WORKUP
   β-hCG (always first), CBC + ferritin/iron studies, TSH, transvaginal ultrasound (first-line imaging: structural PALM vs non-structural COEIN). Coagulation/vWD screen ordered if AUB-C history positive (ACOG; Mayo PMID 30711128; Weaver PMID 15845930)
   inputs: beta_hcg, cbc_and_ferritin, tsh, transvaginal_ultrasound
   actions: panel.cbc, panel.iron, panel.tsh, workup.abnormal_uterine_bleeding
   advance: pregnancy excluded; anaemia quantified; TVUS obtained; structural-vs-nonstructural pivot set
6. 6BRANCHING_WORKUP
   CONDITIONAL-DEPENDENCY workup. (1) TVUS focal/thickened → saline-infusion sonography or hysteroscopy: a NON-focal TVUS does NOT exclude a polyp (TVUS polyp sens only 0.51, Maheux-Lacroix PMID 27824761) so SIS is conditioned on (TVUS result × persistent symptom × fertility intent); a positive SIS/hysteroscopy for a submucosal leiomyoma is near-diagnostic — SIS LR+ 29.7 (95 % CI 17.8–49.6), hysteroscopy LR+ 29.4 (13.4–65.3), hysteroscopy NEGATIVE LR− 0.07 (Farquhar PMID 12780419) → route directly to operative hysteroscopy. (2) Endometrial biopsy yield is conditioned on age + unopposed-oestrogen prior (PMB EC prior 7.7 %, Long PMID 32008795; pre-menopausal <1 % unless age ≥ 45 / obesity / PCOS / Lynch / tamoxifen / persistent-or-failed-Rx, Mayo PMID 30711128). (3) TVUS endometrial-thickness LR is conditioned on menopausal status + exogenous hormones: same 5-mm cut-off LR+ 12 off-HRT vs 4.2 on-HRT (Smith-Bindman PMID 9809732) and 1.47 on tamoxifen (Weaver PMID 15845930). (4) vWF-assay post-test is conditioned on the structured-history screen (sens 82→95 % with PBAC, Philipp PMID 18226613) AND the age prior (39 % adolescent vs 16 % adult, Comishen PMID 39617186). AUB-O → androgen/PCOS workup (SOGC PMID 25767949)
   inputs: saline_infusion_sonography_or_hysteroscopy, endometrial_biopsy, coagulation_vwf_panel
   actions: panel.coag, panel.hormone, calc.palm_coein
   advance: focal lesion localised if present (SIS LR+ ≈ 30 for submucous fibroid → operative route); endometrial histology obtained if age/risk threshold met; coagulopathy/ovulatory subtype resolved
7. 7DIFFERENTIAL
   Assign PALM-COEIN class(es): structural PALM (Polyp / Adenomyosis / Leiomyoma FIGO 0–8 / Malignancy-hyperplasia) vs non-structural COEIN (Coagulopathy / Ovulatory dysfunction / Endometrial / Iatrogenic / Not classified). MECE pivot = TVUS/SIS (structural?) → biopsy (malignant?) → coagulation (bleeding disorder?) → cycle history (ovulatory?). Causes coexist — classify additively (Munro PMID 21345435)
   inputs: transvaginal_ultrasound
   advance: one or more PALM-COEIN classes assigned (additive)
8. 8RISK_STRATIFICATION
   calc.palm_coein → cause class drives medical-first (COEIN) vs procedural (PALM focal) routing. calc.us_mec → hormonal-therapy eligibility — the SAME option flips Category 1→4 by US-MEC comorbidity vector (migraine-with-aura/VTE/thrombophilia/breast-cancer/cirrhosis/SLE-aPL), substituting progestin-only/LNG-IUD (conditional dependency; Nguyen PMID 39106314). T_test (biopsy) crossed by age ≥ 45 y OR unopposed-oestrogen risk OR persistent/failed-Rx (a positive TVUS LR+ ≈ 1.5–2 is too weak to be a treat threshold; biopsy mandatory once prior crosses). T_treat (acute) = orthostasis/SBP<90/HR>110 → ED. T_treat (chronic) = treat-to-target acceptable bleeding + corrected Hb/ferritin (ECLIPSE PMID 26507206). Anaemia severity → transfusion/pre-op correction (ACOG CO 557 PMID 23635706; SOGC PMID 25767949)
   inputs: age, us_mec_comorbidities
   actions: calc.palm_coein, calc.us_mec
   advance: cause class + hormonal eligibility + biopsy decision threshold + disposition route set
9. 9TREATMENT
   ACUTE heavy AUB (stable): IV conjugated equine oestrogen 25 mg q4–6h, OR high-dose monophasic COC taper, OR oral medroxyprogesterone, OR tranexamic acid 1.3 g PO TID (or 1 g IV); D&C / hysteroscopy / intrauterine tamponade if unstable or medical failure (ACOG CO 557 PMID 23635706). CHRONIC HMB treat-to-target (acceptable bleeding + corrected anaemia): LNG-IUS 52 mg FIRST-LINE — superior to usual medical Rx (ECLIPSE MMAS MD 13.4 over 2 y, PMID 26507206), superior to COC (Cochrane MBL OR 0.21, PMID 30742315) and to TXA (PMID 29656433); then COC (success 12→77 %, PMID 30742315), long-cycle oral progestin (PMID 23595582), tranexamic acid (−53 mL/cycle, 34–59 %, PMID 29656433/21767224/20859150), NSAID (naproxen/mefenamic acid). STRUCTURAL: hysteroscopic polypectomy/myomectomy for focal intracavitary, UAE or myomectomy or GnRH-agonist bridge for leiomyoma, LNG-IUS/dienogest/GnRH for adenomyosis (SOGC PMID 25767949/37244746); endometrial ablation or hysterectomy if childbearing complete. Hormonal options gated by US-MEC (PMID 39106314). Bleeding-disorder: TXA + hormonal + haematology ± vWF concentrate (PMID 31886837/37385272). Iron repletion (PO ferrous sulfate alternate-day, IV iron if severe/intolerant) throughout
   inputs: beta_hcg, reproductive_intent, us_mec_comorbidities
   advance: acute haemostasis achieved if applicable AND chronic treat-to-target plan + iron repletion + comorbidity gating documented
10. 10DISPOSITION
    Outpatient for haemodynamically stable AUB. ED / admission for haemodynamic instability, severe symptomatic anaemia requiring transfusion, or acute bleeding refractory to medical therapy needing surgical haemostasis (ACOG CO 557 PMID 23635706)
    inputs: sbp, hr
    advance: level of care set
11. 11MONITORING
    Bleeding diary / PBAC + Hb/ferritin trajectory to treat-to-target. Re-image structural lesions (interval TVUS for leiomyoma/adenomyosis). Endometrial surveillance on progestin therapy for hyperplasia (re-biopsy per histology). Reassess US-MEC eligibility if new comorbidity. LNG-IUS expulsion / unscheduled bleeding check at 3–6 months (ECLIPSE PMID 26507206; SOGC PMID 25767949)
    inputs: cbc_and_ferritin
    actions: panel.cbc, panel.iron
    advance: response confirmed (acceptable bleeding + corrected anaemia) or therapy escalated
12. 12FOLLOWUP
    Treat-to-target sustained — revisit reproductive plan, contraception, and definitive options as fertility intent changes. Continued endometrial-malignancy surveillance for persistent AUB despite therapy (re-biopsy / hysteroscopy). Cross-refer: gyn.dysmenorrhea.core.v1 (overlap adenomyosis/endometriosis pain), endo.pcos.core.v1 (AUB-O cause), gynaecologic oncology if AUB-M. Counsel on long-term anaemia prevention (Jain PMID 37538019; Dutton PMID 36997220)
    advance: long-term plan + surveillance + cross-referrals documented