Baylor College of Medicine Houston, Texas, United States
Background/Case Studies: Intrauterine transfusion (IUT) is a treatment option for hemolytic disease of the fetus and newborn (HDFN) due to maternal alloimmunization. The aim of this study is to compare fetal outcomes amongst mothers with maternal alloimmunization and identify possible predictive values at our tertiary obstetric center.
Study
Design/Methods: We performed a retrospective review of pregnancies requiring IUT between January 2013 and March 2024 at our center. We then selected for completed pregnancies undergoingIUT for maternal alloimmunizationwith fetal outcomes (living or deceased).The electronic medical records were reviewed to include maternal demographics, pregnancy history, alloantibodies, antibody titers, and IUT procedureand laboratory data. Statistical analysis was performed based on fetal outcome using the Mann-Whitney U test for comparison of means between the two groupsusing SPSS version 27 (IBM, NY).
Results/Findings: We identified 33 pregnancies (29 patients, 119 IUT procedures)for evaluation with a survival rate of 88%.Anti-D was identified as the primary antibody in 23 pregnancies with a median titer of 256. Concurrent anti-C was present in 11. Other antibodies identified in patients with anti-D included: anti-E (4), anti-G (2), anti-Jka (1), and anti-Jkb (1). Anti-K was the primary antibody in 6 cases with a median titer of 16. Additional antibodies present in patients with anti-K included: anti-E (1) and anti-Jkb (1). Other primary mediators of HDFN in our series included anti-Fya (1, titer 64), anti-c (3, median titer 32), and anti-E (1, titer 64). Notably, three patients developed additional antibodies during IUT including anti-S, anti-Jkb, and anti-C + anti-E. In the fetal demise group, anti-D was present in three patients (two with anti-C) with a median titer of 512.Anti-c (titer 32) and anti-Jka were identified in the last pregnancy with fetal demise. Procedure and laboratory data for IUT are presented in Table 1. There were statistically significant differences between the gestational age at first IUT, presence of fetal hydrops (24% of survivors [n=7] and 100% of fetal demise [n=4], with a p-value of <0.008), initial middle cerebral artery (MCA) velocity in multiples of the mean (MoM), fetal pre-procedurehematocrit, estimated fetal weight per procedure, and post-procedure platelet count. Maternal age and fetal weight at first IUT did not differ significantly between groups. Conclusions: The risk for fetal demise is higher when IUT is performed at an earlier gestational age and with markers of increased severity of fetal anemia. Thesignificant predictors of fetal demisecanbe usefulfor providing prognostic information, patient counseling, andevaluatingfetuses throughout treatment. The identification of new antibodies formed throughout IUT therapy is an important area of future research.
