Antepartum haemorrhage — placenta praevia at 34 weeks

Diagnosis and risk. Major antepartum haemorrhage, with the fingerprint of placenta praevia — painless, bright-red bleeding in the third trimester, with a soft, relaxed, non-tender uterus and a reactive CTG. The two previous Caesarean scars make placenta praevia substantially more likely, and they make the coexisting placenta accreta spectrum the highest-risk additional diagnosis to anticipate. This is a major APH by the RCOG classification — it has produced a significant bleed at a gestation under 37 weeks, with an Rh-negative mother needing anti-D.^[1]

The examination I must NOT perform. A digital vaginal examination. Until placenta praevia is excluded by ultrasound, a digital examination can shear the placental edge from the lower segment and convert a warning bleed into a catastrophic haemorrhage. The safe alternative is a speculum examination, which visualises the cervix and the blood loss without entering the os, combined with transvaginal ultrasound (which is safe and more accurate than transabdominal for localising the placenta). A digital examination only proceeds once the placenta has been "ruled up."^[1]

Immediate management — simultaneous maternal and fetal resuscitation. Call obstetrics, anaesthetics, haematology and neonatology now. Run the ABCDE: high-flow oxygen if shocked, place the mother in a left lateral tilt to relieve aortocaval compression, site two large-bore cannulae (14 or 16 gauge), draw bloods including a full blood count, coagulation with fibrinogen, urea and electrolytes, liver function tests and a venous gas, send a group and save with a crossmatch of 4 units (O-negative blood if the crossmatch is delayed beyond 15 minutes), give balanced crystalloid boluses warmed and titrated to the response, give tranexamic acid 1 g intravenously, and activate the massive transfusion protocol. Apply a continuous CTG and monitor the fetus throughout resuscitation.^[1]

Anti-D and the Kleihauer-Betke. This mother is RhD negative — send a Kleihauer-Betke (or flow cytometry) to quantify any fetomaternal haemorrhage, and give anti-D immunoglobulin 500 IU intramuscularly within 72 hours, with additional anti-D dosed from the Kleihauer result if the fetomaternal haemorrhage is significant.^[1][4]

Corticosteroids. At 34 weeks she is within the window for antenatal corticosteroids — give betamethasone 12 mg intramuscularly, two doses 24 hours apart, provided the maternal condition is stable enough to allow the 48 hours.^[3]

Anticipating accreta and the definitive plan. Praevia with two previous Caesarean scars carries a high risk of placenta accreta spectrum. Pre-alert the senior obstetrician, the anaesthetic team, the interventional radiology service and the cell salvage, and obtain consent for Caesarean section that includes consent for hysterectomy. The definitive management is Caesarean section — elective at 37 weeks if she stabilises, or emergency now if the bleeding is ongoing or she deteriorates. There is no role for vaginal delivery when the placenta covers the os.^[2]

Disposition. Labour ward or theatre with the full obstetric and anaesthetic team; high-dependency post-delivery if she has been transfused or shocked.^[1]