The Rh test is a blood test. It checks your blood for a marker called Rh. If you have Rh-negative blood and your baby has Rh-positive blood, your immune system may make antibodies that can harm your baby. When a pregnant woman has these antibodies, it is called Rh sensitization.
The Rh test is done in early pregnancy to find out if your baby is at risk for Rh disease. This can happen if you have Rh-negative blood and your baby has Rh-positive blood. If your Rh-negative blood mixes with Rh-positive blood, your immune system will make antibodies to attack the Rh-positive blood.
During pregnancy, these antibodies could attach to the baby's red blood cells. This can cause your baby to have serious health problems.
You do not need to do anything before you have this test.
A health professional takes a sample of your blood.
Rh sensitization does not cause any warning symptoms. A blood test is the only way to know if you are at risk for it.
Watch closely for changes in your health, and be sure to contact your doctor, midwife, or nurse call line if you have any problems.
Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor, midwife, or nurse call line if you are having problems. It's also a good idea to keep a list of the medicines you take. Ask your doctor or midwife when you can expect to have your test results.
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Current as of: March 16, 2017
Adam Husney, MD - Family Medicine
& Kirtly Jones, MD - Obstetrics and Gynecology
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