Rh (Rhesus) factor is not a blood type by itself. It is a factor that is added to your main blood type. How blood typing works Your full blood type has two parts: \t1.\tABO group: \t\tA, B, AB, O \t 2.\tRh factor: \t\tPositive ( ) → Rh present \t\tNegative (–) → Rh absent So your actual blood type is one of these: \t\tA or A– \t\tB or B– \t\tAB or AB– \t\tO or O– Saying “I’m Rh negative” is incomplete. It tells the Rh factor, but not the ABO group. For example, she could be: \t•\tO– \t•\tA– \t•\

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