Evaluation of a non-invasive test for fetal RhD genotype

Women that have Rh negative blood require special tests to determine fetal blood type. The need for treatment during pregnancy in a woman with Rh negative blood depends partly on the baby’s blood type.  In rare cases, unborn babies of women who are Rh negative can develop low red blood cells (anemia) during the pregnancy and may need treatment for this. Currently in North America determining baby’s blood type during pregnancy is done by chorionic villus sampling or by amniocentesis. These invasive procedures have risks of premature labor, premature rupture of the membranes and infection. This study will be done in women who have Rh negative blood to test a non-invasive method of determining the Rh type and sex of the baby using the baby’s genetic material that is found in the mother’s blood during pregnancy.  This method is being used in Europe but needs to be tested here before it can be used in North America.


  1. To evaluate the performance of a reagent kit that uses cell free fetal DNA in the maternal circulation to accurately predict the fetal RhD genotype with the MassARRAY™ system.
  2. To identify the earliest time point in pregnancy for which accurate fetal RhD genotype results can be coordinated with routine prenatal serum testing. 

This prospective observational study is a multi-center investigation involving the collection of blood from pregnant women at 16 sites that are members of the North American Fetal Treatment Network (NAFTnet). The Baylor College of Medicine (BCM) is coordinating the data collection and sample analysis for this study.  The required sample size is 640 women. Pregnant women known to be RhD negative who present to the MUHC-RVH Prenatal Blood Test Centre in the first trimester will be invited to participate

Sponsored by Sequenom

Principal investigator Dr Kenneth Moise, Baylor College of Medecine, Texas
MUHC site Principal Investigator Dr Richard Brown profile; Co-Investigator Angela Mallozzi profile
Study coordinators  Jennifer  Snyder,Tel: 514-934-1934 x 31761  Beatrice Stoklas, Tel: 514-934-1934 x 34074