(981) The effect of maternal blood transfusion history on alloimmunized pregnancies

Friday, January 31, 2025

4:00 PM – 6:00 PM

Submitting Author and Presenting Author(s)

Brittany J. Arkerson, MD

Maternal-Fetal Medicine Fellow
Indiana University
Indianapolis, Indiana, United States

Coauthor(s)

Faezeh Aghajani, MD

Postdoctoral Research Fellow
Fetal Care and Surgery Center, Division of Fetal Medicine and Surgery, Boston Children’s Hospital and Harvard School of Medicine
Boston, MA, United States
EM

Evelyn McGuire

Medical Student
Indiana University School of Medicine
Indianapolis, Indiana, United States
KM

Katherine Modrall

Medical Student
Indiana University School of Medicine
Indianapolis, Indiana, United States
LS

Lucy Salter

Medical Student
Indiana University School of Medicine
Indianapolis, Indiana, United States
AS

Anthony L. Shanks, MD, MEd

Vice Chair of Education & MFM Fellowship Director
Indiana University School of Medicine
Indianapolis, Indiana, United States
Hiba J. Mustafa, MD (she/her/hers)

Director of Fetal Surgery, Director of Placenta Accreta Spectrum Program
Indiana University and Riley Children's Hospital
Indianapolis, IN, United States

Objective: To evaluate the impact of prior blood transfusion on diagnosis and severity of maternal alloimmunization.

Study Design: A single-center retrospective cohort study of alloimmunized singleton gestations with antibodies known to be associated with hemolytic disease of the fetus and newborn (HDFN) from 2018 to 2023. We excluded pregnancies if the fetus was determined to be not at risk for HDFN either by negative paternal genotyping or negative invasive diagnostic testing. Multiple gestations were excluded as well. Univariate and multivariate analyses were performed. P-value < 0.05 was considered statistically significant.

Results: 76 patients with alloimmunization were identified who had a documented history of blood transfusion. 40 patients had no prior history of blood transfusion while 36 did report a prior transfusion. The type of antibody present differed significantly between the two groups. Patients with a history of blood transfusion presented with a wider variety of antibodies than those who did not. Patients with a history of blood transfusion predominantly presented with anti-K, whereas those without prior blood transfusion history presented with primarily anti-D. Both groups were equally likely to have more than one antibody present. Patients with a history of blood transfusion had their first titer drawn at a later gestational age (11.02 ± 2.2 vs. 9.6 ± 2.3). However, there was no significant difference between the maximum antibody titer reached during pregnancy (101.5 ± 251.3 vs. 220.2 ± 475.5). Moreover, both groups were equally likely to have MCA Dopplers initiated, reach maximum MCA PSV MoM ≥1.5, and require IUT.

Conclusion: Patients who develop alloimmunization due to blood transfusion are more likely to present with a wider variety of antibodies but this does not impact the need for MCA Doppler monitoring or IUT in a clinically significant way.