A 32-year-old G3P2 woman at 35 weeks' gestation has a past medical history significant for hypertension. She was well-controlled on hydrochlorothiazide and lisinopril as an outpatient, but these drugs were discontinued when she found out that she was pregnant. Her blood pressure has been relatively well controlled in the 120-130 mm Hg systolic range without medication, and urinalysis has consistently been negative for proteinuria at each of her prenatal visits. She presents now to the obstetric clinic with a blood pressure of 142/84 mm Hg. A 24-hour urine specimen yields 0.35 g of proteinuria.Which of the following is the most appropriate next step?