A 32-year-old multigravida (G3P2) at 28 weeks of gestation is referred from a peripheral health center with a blood pressure of 152/96 mmHg on two occasions 4 hours apart. She denies headache, visual disturbances, or epigastric pain. Urine dipstick shows 1+ proteinuria. Platelet count is 250,000/μL, serum creatinine is 0.9 mg/dL, and liver enzymes are normal. Fetal biophysical profile is 8/8. What is the most appropriate next step?