
Fetal blood sampling, or percutaneous umbilical blood sampling (PUBS), is a diagnostic test that takes blood directly from the umbilical cord during pregnancy. This test gives more detail to check for any possible fetal complications.
Why is fetal blood sampling done?
Why is fetal blood sampling done?
Fetal blood sampling, or PUBS, is done at about 18 to 19 weeks of pregnancy to evaluate for several different fetal conditions. The test is typically used when less invasive tests or procedures, such as chorionic villus sampling (CVS) or amniocentesis, are unavailable or have not provided conclusive results.
PUBS is often used to diagnose blood disorders, like fetal anemia, but it can also diagnose fetal infections, such as toxoplasmosis, and certain genetic conditions. During the test, your doctor can perform a blood transfusion or deliver medications to your baby without inserting another needle.
Within the Fetal Center at Riley Children’s Health, the highly skilled maternal-fetal medicine physicians specializing in fetal intervention perform this delicate procedure. Our specialists have extensive training and experience and partner with a multidisciplinary team to offer compassionate and expert care. Riley Children’s has performed PUBS for over a decade.
Are there any risks with fetal blood sampling?
Since fetal blood sampling is an invasive procedure, it does come with some risks. These risks include:
- Bleeding
- Infection to the mother, baby, or both
- Preterm labor
- Preterm birth
- Premature rupture of membranes (PROM)
While there are risks, some benefits of fetal blood sampling include:
- Knowing specific information about your baby’s health
- The ability to treat a fetus during pregnancy with certain conditions like fetal anemia
If the doctor thinks your baby might be anemic (low blood count) or low platelet count, this test is the only way to know because it tests the baby’s blood rather than amniotic fluid. If the baby needs a blood transfusion or fluids during the same test, the doctor can give those while the same needle is still in the umbilical cord.
Your doctor may recommend this test if:
- An abnormality was found on a prenatal ultrasound
- Results from other tests are not certain
- Rh incompatibility is an issue
- Your baby might have an infection (such as toxoplasmosis)
What to Expect
What to Expect
Preparing for your procedure
Before your scheduled procedure, you will be instructed not to eat or drink anything after midnight the evening before your appointment. When you arrive at the Riley Maternity Tower, your healthcare team will get you checked in. They may give steroid injections as a precaution to help develop your baby’s lungs if an emergency C-section is needed. You will also receive antibiotics to help lower the chance of an infection.
With the risk of needing an emergency C-section, our team takes extra steps to prepare. Your fetal blood sampling procedure will occur near an operating room, with team members from labor and delivery, anesthesiology and neonatology made aware of the procedure. If you need an emergency delivery, be assured that your healthcare team is ready.
What happens after fetal blood sampling?
After your procedure, you’ll need to rest in the hospital while your baby’s heart rate and other vitals are monitored over a few hours. Typically, you can leave later in the day after the procedure is performed, but you will need to have someone drive you home.
The results typically take several days to come back. You will have a follow-up appointment with Riley Maternal-Fetal Medicine or Fetal Center within a week of the procedure.
Key Points to Remember
Key Points to Remember
- Fetal blood sampling, or PUBS, is a diagnostic test during pregnancy that’s used when other more common tests like CVS or amniocentesis are not an option or have given inconclusive results
- While there are risks, the benefits can include getting more detailed information about your baby’s health and the ability to treat severe blood disorders before birth
- The Riley Maternity Tower provides access to all necessary specialties for both mom and baby to ensure coordination of care in the unlikely event a complication occurs
Locations
Locations
Locations
Riley Maternity Tower
702 Barnhill Dr
Indianapolis, IN 46202
Fetal Center at Riley Children's Health
575 Riley Hospital Dr
Indianapolis, IN 46202
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