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obstetrics surgery

Placenta Praevia / Accreta Risk Assessment

Assesses risk of placenta praevia and placenta accreta spectrum (PAS) disorder. Guides third trimester USS and surgical planning.

Used in: Pre-eclampsia & Obstetric Emergencies

Score interpretation

Low risk

→ Routine antenatal care; repeat USS at 32 weeks if low-lying at 20 weeks; reassurance if fundal/posterior; standard delivery planning

Moderate risk — targeted surveillance

→ Transvaginal USS at 32-34 weeks; if anterior low praevia with prior CS: MRI pelvis to exclude accreta; consultant-led care; cross-match blood; delivery at 36-37 weeks with senior team

High risk — accreta/praevia planning

→ Tertiary obstetric centre; MRI pelvis; multidisciplinary team (obs, urology, interventional radiology, blood bank); planned CS at 34-36 weeks; 6-10 units blood on standby; cell salvage; interventional radiology balloon occlusion; consent for hysterectomy

Interpretation bands for the Placenta Praevia Risk. Apply clinical judgement and local guidance.

References

Related

Curated clinical cross-links plus same-class fallbacks.

Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.