Early-Onset Preeclampsia

Early onset preeclampsia is preeclampsia diagnosed before 34 weeks of pregnancy. It is driven by severe placental dysfunction and is usually associated with fetal growth restriction and abnormal uterine and umbilical artery Doppler. It matters because it carries high maternal morbidity and perinatal mortality, and the timing of delivery balances maternal risk against fetal immaturity.

• Less common than late onset disease.
• Risk factors: previous early preeclampsia, antiphospholipid syndrome, chronic hypertension, kidney disease, lupus.
• Delay in delivery is considered only in tertiary units with intensive monitoring.

Women have hypertension and proteinuria before 34 weeks, often with a small fundal height, reduced fetal movements, headache or epigastric pain.

• Small for dates uterus.
• Oligohydramnios on scan.
• Differential diagnosis: chronic hypertension with superimposed preeclampsia, lupus nephritis, antiphospholipid syndrome, thrombotic thrombocytopenic purpura, HELLP syndrome, fatty liver of pregnancy, molar pregnancy with preeclampsia.
• Complications: fetal growth restriction, stillbirth, extreme preterm birth, abruption, eclampsia, HELLP syndrome, maternal stroke, neonatal death.

The diagnosis follows the standard criteria, with fetal assessment to guide delay or delivery.

• Blood pressure 140/90 mmHg or more twice, 4 hours apart, with proteinuria or organ dysfunction before 34 weeks.
• Full blood count, creatinine, liver enzymes, lactate dehydrogenase, uric acid, coagulation screen, urine protein to creatinine ratio, antiphospholipid antibodies and lupus tests.
• Ultrasound for growth, liquor volume, umbilical artery and middle cerebral artery Doppler, ductus venosus Doppler; cardiotocography.
• Uterine artery Doppler showing a notch and high resistance supports a placental cause.

The principle is maternal stabilisation with steroids and magnesium, and delivery at the point where maternal or fetal condition requires it.

• Supportive: admit in a facility with a neonatal intensive care unit; left lateral position; strict fluid limit of 80 mL per hour when severe; hourly urine output; blood pressure every 15 minutes during acute treatment, then 4-hourly.
• Pharmacological: 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) or methyldopa 250 to 500 mg oral 8-hourly (maximum 3 g daily) for blood pressure 140/90 mmHg or more; for 160/110 mmHg or more give labetalol 20 mg IV over 2 minutes then 40 mg, 80 mg and 80 mg at 10 minute intervals (maximum 220 mg) or nifedipine immediate release 10 mg oral repeated after 30 minutes or hydralazine 5 mg IV then 5 to 10 mg every 20 to 30 minutes (maximum 20 mg); betamethasone 12 mg IM twice, 24 hours apart, from 24 to 34 weeks; magnesium sulphate 4 g IV over 20 minutes then 1 g per hour for 24 hours for severe features and for neuroprotection before 32 weeks; aspirin 150 mg oral at night from 12 weeks to 36 weeks in a future pregnancy; oxytocin 10 IU IM after birth.
• Procedures: delivery by caesarean section or induction at once for eclampsia, abruption, pulmonary oedema, uncontrolled hypertension, HELLP syndrome, reversed end diastolic flow or abnormal cardiotocography; otherwise delay for 48 hours to complete steroids; delivery by 34 weeks for severe disease.
• Special groups: antiphospholipid syndrome needs enoxaparin 40 mg subcutaneous daily with aspirin; kidney disease reduces magnesium sulphate to 0.5 g per hour with level monitoring.
• Red flags: blood pressure 160/110 mmHg or more, seizure, headache, epigastric pain, platelets below 100 x 10^9/L, absent or reversed end diastolic flow, reduced fetal movements.
• Follow-up: inpatient blood tests every 12 to 24 hours; Doppler and growth scans twice weekly to weekly; postnatal blood pressure checks; counselling about the high risk of recurrence and aspirin from 12 weeks in a future pregnancy.