Hi mama! BPS means Biophysical Profile Score, it's basically a detailed ultrasound check to make sure baby is doing okay, looking at movements, breathing, amniotic fluid, and muscle tone, so super reassuring talaga! Your doctor requested it early at 28 weeks probably because she wants extra peace of mind based on your pregnancy, and yes it's completely safe, it's just an ultrasound, no radiation or anything harmful, so don't worry. A few of us got it done earlier than usual din and honestly it's one of those things na nakakabigay ng extra confidence na lahat's good with baby. Go ahead with it, mama, it's all good!