RHD NIPT

Rhesus D non-invasive prenatal testing (RHD NIPT)

The RHD NIPT is a screening test that looks at your baby's DNA that is found in your blood. It is specifically recommended for all pregnant patients with Rhesus D negative blood type to determine if your baby is likely to have Rhesus positive or negative blood type.

If you have Rhesus negative blood type and your baby has Rhesus positive blood type, there is a possibility that your body could produce antibodies that cause harm to your current pregnancy and future ones.

This can be prevented by screening and a medication called Rhesus D Immunoglobulin (RhD Ig), also known as anti-D. However, if both you and your baby are Rhesus negative, anti-D is not needed.

The RHD NIPT can be requested by your treating doctor and the test result can be used to decide if you need the anti-D medication. 

If you are Medicare-eligible, there is no out-of-pocket cost to you for this test.

Keep in mind, this is a separate test to the non-invasive prenatal testing (NIPT) that is used to screen for chromosomal abnormalities or other genetic conditions. The two tests are done for different reasons and your doctor may recommend one or both tests (if eligible).

Why is this testing important for Rhesus negative pregnant patients and their babies?

If you are RhD negative - and only if your baby is RhD positive - your body may make antibodies against your baby's blood Rhesus D group. These antibodies do not usually cause harm in your first pregnancy, however, if your next baby is also RhD positive, these antibodies may damage the baby's blood cells and cause a severe disease called haemolyctic disease of the fetus and newborn (HDFN).

How do I get the RHD NIPT done at PathWest?

The RHD NIPT must be requested by your doctor and involves blood testing between 20 and 32 weeks of pregnancy. Your doctor will need to complete the request form with information including your expected delivery date, number of fetuses and body mass index.

Results usually take two weeks. Make an appointment with your doctor or endorsed midwife to discuss the results.

What if I choose not to have the test or miss the 20-to-32 week test window?

In these situations, you will be treated as though your baby is RhD positive and it will be recommended that you receive the anti-D injection. This is the safest choice to ensure the wellbeing of your baby.

Further reading and resources

Download this guide to learn more about the RHD NIPT or download the RHD NIPT request form.

Testing at a glance

Rhesus D Non-Invasive Prenatal Testing (RHD NIPT)

Conditions screened: Fetal Rhesus blood genotype testing

When to test: Recommended in pregnant patients who are Rhesus negative and do not have anti-D antibodies. Testing can be performed at 20-32 weeks gestation. Referrals for testing before 20 weeks or after 32 weeks are not accepted

Turnaround time: 2 weeks

Cost: Medicare-funded tested (Item no. 73420). No out-of-pocket costs if Medicare-eligible.

Arranging: Can be ordered by registered medical practioners (doctors). This requires a separate request form. Please provide the following:

  • Clearly state patient is Rhesus D negative
  • Expected date of delivery (requests are not accepted before 20 weeks and after 32 weeks gestation
  • Singleton or multiple pregnancy (number of fetuses)
  • Body mass index (BMI)

Collection: Blood sample at PathWest collection centres.

Testing: Only performed in Rhesus D negative pregnant women with no known anti-D antibodies. This screening test (RHD NIPT) is different to the non-invasive prenatal test (NIPT) that is used to screen for chromosomal abnormalities or other genetic conditions.

Results: Results are delivered to the requested healthcare provider and MyHealthRecord unless otherwise indicated

  

 

 

 

 

Last Updated: 07/11/2024