Chronic Placental Abruption

Chronic placental abruption is long-standing low-grade separation of the placenta, with repeated small bleeds, giving intermittent dark vaginal discharge, oligohydramnios and fetal growth restriction. It results from chronic decidual vasculopathy, thrombophilia, hypertension or an unexplained cause, and it often accompanies chronic hypertension and previous preterm rupture. It matters because it is easily missed, it reduces placental function and it leads to preterm birth and stillbirth.

• Associated with the chronic abruption oligohydramnios sequence.
• Risk factors: chronic hypertension, thrombophilia, smoking, previous abruption, recurrent bleeding in early pregnancy.
• Perinatal mortality is raised and survival depends on gestation at birth.

Women have repeated light dark brown or red bleeding, sometimes for weeks, with mild intermittent abdominal pain, and a small fundal height. Fetal movements may be reduced.

• Intermittent staining for 2 weeks or more.
• Small abdomen for dates.
• Differential diagnosis: placenta previa, cervical polyp or ectropion, vaginal infection, early membrane rupture, subchorionic haemorrhage, cervical cancer.
• Complications: oligohydramnios, fetal growth restriction, preterm labour, premature rupture of membranes, acute abruption, stillbirth, anaemia, pulmonary hypoplasia.

The approach is serial ultrasound with clinical history of repeated bleeding.

• Ultrasound: retroplacental or marginal clot, thickened placenta, oligohydramnios, growth below the 10th centile, abnormal umbilical artery Doppler; placental position to exclude previa.
• Haemoglobin, platelets, fibrinogen, coagulation screen, creatinine, urine protein; antiphospholipid antibodies and thrombophilia tests.
• Speculum examination for the source of bleeding once previa is excluded.
• Cardiotocography twice weekly from 28 weeks; Kleihauer test in RhD negative women.

The principle is expectant care with close fetal surveillance, steroids and delivery by 37 weeks, earlier for compromise.

• Supportive: admit during bleeding episodes; rest; stop smoking; avoid intercourse; daily fetal movement counts; blood in the bank; two cannulae in any heavy bleed.
• Pharmacological: ferrous sulphate 200 mg oral 8-hourly; aspirin 150 mg oral at night from 12 weeks to 36 weeks in the next pregnancy; enoxaparin 40 mg subcutaneous daily with aspirin 150 mg oral at night for antiphospholipid syndrome; labetalol 200 mg oral every 8 to 12 hours (maximum 2.4 g daily) or nifedipine modified release 30 to 60 mg oral once daily (maximum 120 mg) for blood pressure 140/90 mmHg or more; betamethasone 12 mg IM twice, 24 hours apart, between 24 and 34 weeks and 6 days when delivery is likely; magnesium sulphate 4 g IV over 20 minutes then 1 g per hour until delivery for 24 hours at most before 32 weeks; tranexamic acid 1 g IV over 10 minutes for acute bleeds; oxytocin 10 IU IM at birth.
• Procedures: delivery by induction or caesarean section at 37 weeks, earlier for growth restriction with abnormal Doppler, pathological cardiotocography or acute abruption; amnioinfusion in labour for variable decelerations with oligohydramnios.
• Special groups: RhD negative women give anti-D immunoglobulin 500 IU IM within 72 hours of each bleed; newborns have glucose checked at 2 hours, with glucose below 2.6 mmol/L treated by dextrose 10 percent 2 mL/kg IV over 10 minutes then 80 mL/kg per day.
• Red flags: heavy bleeding, constant pain, reduced fetal movements, absent or reversed end diastolic flow, amniotic fluid index 5 cm or below, contractions, shock.
• Follow-up: growth scan and Doppler every 2 weeks; cardiotocography twice weekly; haemoglobin every 4 weeks; antenatal review weekly from 34 weeks; neonatal review.