Flowchart of identification of high-risk HDFN and FNAIT cases. After high-risk cases are identified using laboratory testing, for both HDFN and FNAIT, fetal ultrasounds are made to look for signs for fetal anemia (HDFN) and bleeding, in particular in the brain (FNAIT). ∗In some countries, HPA-1a antibody quantification is performed for FNAIT. ^†ADCC only for red cell antibodies in the Netherlands. ^‡Fetal ultrasound does not indicate start IV immunoglobulin (IVIg), this is solely done for monitoring possible bleeding. ADCC, antibody-dependent cell-mediated cytotoxicity; MCA-PSV, middle cerebral artery peak systolic velocity.