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Placenta praevia & accreta
Diagnosis and timing of birth.
Source: RCOG GTG 27aDefinitions
| Low-lying | Edge <20 mm from internal os (after 16 wk). |
|---|---|
| Praevia | Covers the os. |
Plan
- Low at 20 wk: TVS at 32 wk; if persists, ~36 wk
- Previous CS + anterior low placenta: screen for accreta
Birth
| Uncomplicated praevia | 36+0–37+0 wk |
|---|---|
| Bleeding history | 34+0–36+6 wk |
| Accreta spectrum | 35+0–36+6 wk |
A summary for trained clinicians. Always check the full guideline, the patient in front of you and your hospital's protocol. Spotted an error? Tell us.