A 28-year-old primigravida from rural Maharashtra presents at 32 weeks of gestation with complaints of decreased fetal movements for 3 days. On examination, fundal height is 28 cm (less than expected for 32 weeks). Vital signs are stable. Doppler ultrasound shows abdominal circumference (AC) <10th centile, estimated fetal weight 1400 g (<10th centile for gestational age), and umbilical artery pulsatility index (PI) 1.8 (elevated). Amniotic fluid volume is normal. There is no evidence of fetal anomalies or maternal infection. What is the most appropriate next step in management?