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Short answer How ABO incompatibility is handled Common questions Related questions SourcesIt depends on the setting: ABO incompatibility in a newborn is usually mild and very treatable, while an ABO mismatched blood transfusion is a medical emergency.
The newborn form happens when a mother with type O blood carries a baby with type A or B blood, and her antibodies break down some of the baby's red cells. That most often shows up as jaundice in the first day or two of life, sometimes with mild anemia, and phototherapy plus good feeding usually handles it. The transfusion form is different, because a large volume of mismatched red cells can be destroyed at once and strain the kidneys. Hospitals prevent it with blood typing, crossmatching, and bedside identity checks before the bag is started. Blood type testing in pregnancy and clear jaundice follow up after birth are the two habits that matter most.
How ABO incompatibility is handled
Common questions
Is ABO incompatibility serious?
It depends on the setting. In newborns, ABO incompatibility happens when a mother with type O blood carries a baby with type A or B blood, and the usual result is mild jaundice and anemia in the first days of life. Most babies do well with monitoring and phototherapy, and a few need extra feeding support or, rarely, an exchange transfusion. In a blood transfusion, ABO incompatibility is a medical emergency, because mismatched red cells can be destroyed quickly and damage the kidneys. Hospitals prevent this with blood typing, crossmatching, and bedside identity checks. Call your baby's doctor if jaundice appears in the first 24 hours or keeps deepening.