A biophysical profile is used to evaluate and monitor a baby's health. The goal of a biophysical profile is to prevent pregnancy loss and detect fetal hypoxia — when the baby is deprived of an adequate oxygen supply — early enough so that the baby can be delivered and not sustain permanent damage.

The test is most commonly done when there's an increased risk of pregnancy loss. Your health care provider will determine the necessity and timing of a biophysical profile based on whether your baby could survive if delivered early, the severity of your condition and the risk of pregnancy loss.

Your health care provider might initially recommend a modified biophysical profile — a simplified version of the test that includes a nonstress test and assesses amniotic fluid through ultrasound. Your health care provider will then use the results to determine whether you need a full biophysical profile, which also measures a baby's breathing, movements and muscle tone.

Your health care provider might recommend a biophysical profile if you have:

  • A multiple pregnancy
  • An underlying medical condition, such as type 1 diabetes, gestational diabetes, high blood pressure, a blood disorder, lupus, thyroid disease, kidney disease or heart disease
  • A pregnancy that has extended two weeks past your due date (postterm pregnancy)
  • A history of pregnancy loss
  • A baby who has decreased fetal movements or possible fetal growth problems
  • Too much amniotic fluid (polyhydramnios) or low amniotic fluid (oligohydramnios)
  • Rh (rhesus) sensitization — a potentially serious condition that can occur when your blood group is Rh negative and your baby's blood group is Rh positive
  • Worrisome results from other prenatal tests

Your health care provider might also recommend a biophysical profile if you're between 40 and 42 weeks pregnant. The benefits of having the test done during this period, however, aren't clear.

Your health care provider might recommend that you have a biophysical profile once a week, twice a week or, rarely, even more frequently — depending on your health condition — until you give birth.

Feb. 22, 2012