Additional file 1: Table S1. General Characteristics of Studies and Patient Groups. Table S2. Research Questions Relevant to Mothers and Fetuses. Table S3. Inclusion and Exclusion Criteriaa. Table S4a. Methodologic Quality of Selected Case Reports. Table S4b. Methodologic Quality of Selected Case Series. Table S4c. Methodologic Quality of Selected Retrospective Cohort Studies. Table S4d. Methodologic Quality of Selected Prospective Cohort Studies. Table S4e. Methodologic Quality of Bennardello et al (25). Table S5. Antenatal Treatments Reported in Studies With Representative Data. Table S6. Hydrops Fetalis, Severe Fetal Anemia, and Adverse Events/Complications Reported in Studies With Representative Data. Table S7. IVIG Treatment Response and Associated Mortality. Table S8. Overall Fetal Mortality Associated With HDFN. Figure S1. Mean Rate of Procedure-related Complications After IUT (Per Procedure [A] and Per Fetus [B]).12,26,30,32,43,44,46,49,52,60 CS, cesarean section; IUT, intrauterine transfusion; PROM, preterm rupture of membranes. aAdverse serological outcome was defined as the development of additional maternal antibodies to anti-D and/or a ≥4-fold enhancement of antibody titer.12. Figure S2. Flowchart of the Article Selection Process for the Humanistic and Economic Burden. SLR, systematic literature review. *From authors’ personal library. †From eligible SLRs of cohort studies.