A 28-year-old multigravida (G3P2) at 35 weeks + 4 days gestation is admitted with vaginal bleeding (approximately 300 mL) and mild lower abdominal discomfort. Vital signs: BP 110/70 mmHg, HR 92/min, RR 18/min. Fetal heart rate is 142/min with normal variability. Transabdominal ultrasound confirms partial placenta previa with the lower placental edge 1.5 cm from the internal cervical os. The patient has had two prior episodes of bleeding in the past 2 weeks, both self-limiting. What is the most appropriate next step in management?