Child Health Library

Healthwise

Our Health Library information does not replace the advice of a doctor. Please be advised that this information is made available to assist our patients to learn more about their health. Our providers may not see and/or treat all topics found herein.

Blood type

Human blood is typed according to whether certain markers, called antigens, are present on the surface of red blood cells. The ABO system classifies blood as type A, B, AB, or O based on the presence or absence of the A and B antigens; the Rh system classifies blood as negative or positive based on the presence or absence of the Rh antigen (Rh factor).

If red blood cells have:

  • The A antigen, they are type A blood.
  • The B antigen, they are type B blood.
  • Both the A and B antigens, they are type AB blood.
  • Neither A nor B antigens, they are type O blood.

Rh blood typing determines the presence (+) or absence (–) of the Rh factor. If red blood cells:

  • Have the Rh antigen, they are Rh-positive.
  • Do not have the Rh antigen, they are Rh-negative.

Current as of: October 7, 2024

Author: Ignite Healthwise, LLC Staff

Clinical Review Board
All Ignite Healthwise, LLC education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

🌞 Summer Camp Forms Reminder!

Help us help you—turn in your forms early!
  • Camp season is here! If your child needs a camp form completed, please submit it as soon as possible.
  • Longer turnaround times are expected due to increased summer volume.
  • Forms can be uploaded through the Patient Portal and will be returned there once completed. Please ensure that all pertinent information is filled out prior to sending or else it will be returned to the caregiver.
  • Submitting early helps us ensure your child is ready for summer fun!