Blood

2 mL; maternal specimen

Specimen must be labeled with patient's first and last name and medical record number. Specimens will be rejected if information is not on the label when received.

24 hrs/day, 7 days a week, including holidays.

2 hours (upon receipt in laboratory)

Negative result means no abnormal amount of fetal red blood cells has been detected in the maternal circulation.

This test is designed to detect patients who may need more than one dose of Rhogam due to a significant fetal bleed. Maternal blood is incubated with anti-D antibodies and indicator cells prior to counting the rosettes (clumps) of RBCs. Fetal blood screening test will only be performed when fetus/infant has been typed as Rh-positive.

Quantitative Fetal Hemoglobin assay will automatically be ordered if the screen is positive. If Fetal hemoglobin is elevated (≥0.3%) then additional RhoGAM is recommended as shown in the table below.

                      % HbF by Flow     Total RhoGAM (vials)
                         < 0.30%                 1
                       0.3% - 0.89%              2
                       0.9% - 1.49%              3
                       1.5% - 2.09%              4
                       2.1% - 2.69%              5
                          >=2.7%        Contact DBC Faculty

This table is generated using conservative estimates of maternal blood volume and Hct (5000 ml blood volume and 50% Hct). The formula to calculate RhoGAM dose is below:

   •(% HbF X 5000)/30 +1. Round appropriately and that is how many vials
     are recommended.

This testing does not detect fetal bleed in a Rh positive female or Rh negative fetus/infant.

Indicator cell rosette test for fetomaternal hemorrhage

86905