Fetal blood sampling is a procedure to take a small amount of blood from an unborn baby (fetus) during pregnancy. Fetal blood sampling is usually done by a perinatologist with special training. This is a doctor who specializes in the care of babies in high-risk pregnancies.
Fetal blood sampling is a very complex procedure. It must be done by a doctor with special training. It’s done when other tests or procedures are not possible or do not work. It can be done for pregnancies that are 18 weeks or later.
Fetal blood sampling is done as part of diagnosing, treating, and checking problems in the baby at certain times during pregnancy. A fetal blood sample may be taken to:
The benefits of fetal blood sampling include:
The risks of fetal blood sampling include:
You don’t need to do any special preparation before the procedure. Your healthcare provider will tell you if you need to have a full bladder for the test.
You will lie in a comfortable position on an exam table. The healthcare provider will clean your belly with antiseptic. He or she will insert a long, thin needle through the belly and into the uterus. This is guided by ultrasound. Blood may be taken from several sites, such as:
Fetal blood transfusions are done using a similar method. The baby either gets blood or has unhealthy blood exchanged for healthy blood. This can treat certain problems. In this case, it may be needed to give a sedative medicine to keep the baby from moving.
After the procedure, you’ll need to rest in the hospital. Your baby’s heart rate will be watched for a few hours. You’ll need to have someone drive you home afterward. The results will take several days. You’ll have a follow-up appointment with the perinatologist to discuss the results.
Before you agree to the test or the procedure make sure you know: