Rhesus D Immune Globulin in Early Pregnancy: A Clinical Review.

This article reviews the actively evolving clinical practice of Rhesus D (RhD) testing and RhD immune globulin (RhIg) prophylaxis in the context of first trimester bleeding events, including abortion. It summarizes population-level data and indirect biologic studies, while comparing current guidelines for RhD testing and RhIg prophylaxis, highlighting existing discrepancies. Considerations such as cost, access, shortages, and fetal RhD status testing via noninvasive prenatal testing are addressed in this discussion. Although several organizations have updated their clinical guidelines to align with recent evidence against RhIg prophylaxis in early pregnancy, more direct clinical data is needed to develop definitive clinical guidance.