What Is The Rh Factor? Why Is It Important?

Blood typing is determined by the molecules on the surface of the red blood cells (RBCs). In general, we can classify someone’s blood type by the absence or presence of A or B antigens and Rh factor on the surface of blood cells. The most commonly recognized blood groups are A positive, A negative, B positive, B negative, AB positive, AB negative, O positive, and O negative.

The positive or negative sign next to the blood groups is known as the Rhesus (Rh) factor. The Rh factor is an inherited protein that can be found on the surface of the red blood cell.

• If your blood type is positive, then your blood cells have the Rh protein.
• If your blood type is negative, then your blood cells lack the Rh protein.

Although Rh positive is the most common blood type, having a Rh-negative typing does not indicate illness and usually doesn’t affect your health.

The Rh factor is one of the proteins on RBCs used to indicate whether the blood of two different people is compatible when mixed – such as blood of a mother and her baby at birth.

It is routine and important that the Rh factor for a mother and unborn child be determined during pregnancy. If an expecting mother is Rh negative and her baby is RH is negative, there aren’t usually any concerns. Conversely if the expecting mother is RH negative and her baby is Rh positive, the mother’s blood might produce the anti-D antibodies. The effect of these antibodies on the development of the unborn child, who is Rh positive, are determined by many factors. There are medical interventions that can be taken under the supervision of a physician to protect the baby in utero.

The Rh factor is important to determine in blood donations and transfusions. A person with the Rh positive factor will not make anti-Rh antibodies. Those with Rh negative factor will produce the antibodies. Therefore, someone with Rh+ blood can receive both Rh+ and Rh- transfusions, but those with Rh- can only receive Rh- blood. Blood type and Rh factor screening are done not only to categorize a blood donation. The Rh screening test result also allows a healthcare provider to give additional support to a patient if incompatibility is detected.

Do you know your Rh factor type? An Rh screening test is a procedure that determines whether the blood cells have the Rh protein on the surface of the blood cell. This exam requires a healthcare professional to collect a sample of blood from a vein in the hand or arm to perform the test. The American Red Cross tests all blood donations for Rh factor along with blood type and various infectious diseases.

Nothing needs to be done to prepare for the screening test. However, to ensure a successful donation make sure to be well rested, well-nourished and hydrated before and after your appointment.