Fetal RHD Screening

Fetal RHD screening is publicly funded for Ontario residents who:

• Are RhD negative
• Do not have anti-D antibodies
• Are pregnant with one baby (not twins or triplets)

Who should not have this test?

Fetal RHD screening is NOT recommended if you:

• Are RhD positive
• Have anti-D antibodies detected in your blood
• Are pregnant with more than one baby
• Started the pregnancy with more than one baby
• Have a known RHD variant or weak D blood type
• Have had a stem cell transplant in the past

Fetal RHD screening can be done as early as 11 weeks in your pregnancy.

·       This test uses a sample of your blood. During pregnancy, small pieces of genetic material from the placenta circulate in your blood. The lab looks at this material to predict your baby’s RhD status.

Your blood can be drawn at a community lab and sent to Canadian Blood Services for testing. Use our map to find a lab near you.

Results are ready in about 10 business days and are sent to your health-care provider.

What if the test cannot give a result?

If the test was unable to give a result, a health-care provider may ask you to repeat the test or treat your pregnancy as if your baby is RhD positive and recommend RhIG treatment.

Learn more about Fetal Blood Type Results & Next Steps

After delivery, a small sample of umbilical cord blood will be collected to confirm your baby’s RhD status. These results may be used to guide newborn care and for laboratory quality checks.