The Rhesus Factor

If your red blood cells contain a substance known as rhesus factor, you are rhesus, or Rh, positive.  If a woman who is Rh negative conceives a baby by a man who is Rh positive and the baby, in turn, is Rh positive, the woman may become sensitized to the Rh positive blood at the time of delivery.  If a subsequent baby is also Rh positive, the mother’s body recognizes the baby’s “foreign” blood and produces antibodies that attack the baby.

Rhesus Factor


First pregnancy

Rh positive blood from the baby enters the mother’s bloodstream.

Rhesus Factor

After first baby

Antibodies develop in the mother to combat Rh positive blood and afterward remain.

Subsequent pregnancies

Rhesus Factor

Antibodies enter subsequent Rh + baby’s blood, causing rhesus hemolytic disease.


The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.

Be the first to comment

Leave a Reply

Your email address will not be published.