A 35-year-old primigravida at 37 weeks’ gestation is found to have blood pressure readings of 148/96 and 146/94 mmHg 4 hours apart. Urine protein is 2+, platelet count and liver enzymes are normal, and she has no headache, visual symptoms or epigastric pain. Ultrasound shows normal growth, liquor and umbilical artery Doppler findings. Which one of the following is the most appropriate next step?