Biophysical Profile (BPP)
How It Is Done
Most often, a biophysical profile (BPP) is performed by your obstetrician. But it may be done by an ultrasound technologist or radiologist. A BPP can be done in your doctor's office, hospital, or clinic.
A nonstress test with electronic fetal heart monitoring and a fetal ultrasound are done as part of a biophysical profile. A nonstress test helps check the baby's health by looking at the baby's heart rate with movement.
Some doctors may use a modified biophysical profile, which combines a nonstress test and measurements of the amniotic fluid (amniotic fluid index).
External fetal heart monitoring records your baby's heart rate while your baby is moving and not moving. It is usually done just before a fetal ultrasound.
External monitoring is done using two flat devices (sensors) held in place with elastic belts on your belly. One sensor uses reflected sound waves (ultrasound) to keep track of your baby's heart rate. The other sensor measures the duration of your contractions. The sensors are connected to a machine that records the information. Your baby's heartbeat may be heard as a beeping sound or printed out on a chart.
If your baby moves or you have a contraction, you may be asked to push a button on the machine. Your baby's heart rate is recorded and compared to the record of movement or your contractions. This test usually lasts about 30 minutes.
Often you do not need to remove your clothes for the ultrasound test; you can lift your shirt and push down the waistband of your skirt or pants. If you are wearing a dress, you will be given a cloth or paper covering to use during the test.
- You may need to have a full bladder. You may be asked to drink 4 to 6 glasses of liquid, usually juice or water, about an hour before the test. A full bladder helps transmit sound waves and pushes the intestines out of the way of the uterus. This makes the ultrasound picture clearer.
- You will not be able to urinate until the test is over. But tell the ultrasound technologist if your bladder is so full that you are in pain.
- If an ultrasound is done during the later part of pregnancy, a full bladder may not be needed. The growing fetus will push the intestines out of the way.
- You will lie on your back on a padded examination table. If you become short of breath or lightheaded while lying on your back, your upper body may be raised or you may be turned on your side.
- A gel will be spread on your belly.
- A small, handheld instrument called a transducer will be pressed against the gel on your skin and moved across your abdomen several times. You may watch the monitor to see the picture of the fetus during the test.
When the test is finished, the gel is cleaned off of your skin. You can urinate as soon as the test is done. Transabdominal ultrasound takes about 30 to 60 minutes.
Ultrasound technologists are trained to gather images of your fetus but can't tell you whether it looks normal or not. Your health professional will share this information with you after the ultrasound images have been reviewed by a radiologist or perinatologist.