This is a non-invasive procedure that involves an ultrasound that looks at four aspects of fetal activity and environment: fetal "breathing", muscle tone, body movements, and amniotic fluid.
Each ultrasound assessment is graded either 0 or 2 points, and then added up to yield a number between 0 and 8. Each variable receives 2 points for a normal response or 0 points for an abnormal or absent response. A BPP of 6 to 8 is generally considered reassuring.
This is then interpreted along with the non-stress test (NST) to determine if the baby is in any danger.