AABB Guide to Prenatal and Postnatal Immunohematology Testing

By Lani Lieberman, MD, FRCP(C); Gwen Clarke, MD, FRCP(C); Mark Fung, MD, PhD; Wen Lu, MD; Theresa A. Nester, MD for the Transfusion Medicine Section Coordinating Committee In the era before neonatal exchange transfusion, intrauterine transfusion, amniocentesis, ultrasonography, and Rh immunoglobulin (RhIG) prophylaxis, Rh(D) hemolytic disease of the fetus and newborn (HDFN) was a major cause of perinatal death. Thanks to these and other key advances the morbidity and mortality associated with Rh(D) HDFN have declined markedly. However, some advances have come with new concerns. For instance, multi-hospital healthcare systems have increased in size and number and hospitals, practitioners, and laboratories have become more specialized. Thus, the caregiver who orders prenatal and perinatal testing may not practice in the same facility where testing is performed. RhIG may not be dispensed by the transfusion service and may fall under the purview of the pharmacy. In this landscape, the management of prenatal and perinatal patients, especially those with a history of sensitization, requires close communication, collaboration, and coordination between clinicians, pharmacists, and transfusion service personnel. The intent of this AABB Guide to Prenatal and Postnatal Immunohematology Testing is to assist in promoting a common understanding among those professionals formulating prenatal and perinatal testing practices and to discourage the use of outdated, non-evidence-based practices and protocols. After laying a solid foundation on the fourfold objectives of prenatal and perinatal testing the Guide provides a thorough exploration of the following key topics: Routine testing during pregnancy, including purpose and timing. Management of the alloimmunized patient, including those with different, non-Rh(D), alloantibodies that can cause HDFN. Testing at delivery for both mother and neonate/cord blood. The use of RhIG prophylaxis, including timing and dose. Where possible, the content is succinctly presented in tabular format. In circumstances where controversies exist or the data are limited or inconsistent, the Guide highlights both pros and cons, encouraging practitioners to keep abreast of future discoveries. DIGITAL EDITION: AABB, 2023