Febrile non-hemolytic transfusion reactions (FNHTRs) are the most common transfusion reaction seen in obstetrics. They occur due to recipient antibodies reacting against donor leukocyte antigens, causing the release of pyrogens and resulting in fever and chills. FNHTRs are generally mild and self-limiting, making them more frequent and less severe than other reactions. In obstetric patients, careful monitoring during transfusion is essential, but these reactions rarely complicate management. Early recognition helps differentiate FNHTR from more severe reactions like hemolysis or anaphylaxis.

Reference: Williams Obstetrics, Cunningham FG, 25th Edition.