The Rh factor is part of your blood type. In addition to being A, B, AB and O, blood can be Rh positive or Rh negative. It is important to know your blood type so you can receive the correct blood type for a transfusion and during pregnancy.
Discovery
Scientists Karl Landsteiner and A. S. Weiner identified the Rh factor in 1940 which connected human blood with that of the rhesus monkey.
Positive vs. Negative
The Rh factor is determined by the antigens present in your blood. Rh positive blood has antigens present, while Rh negative blood does not.
Rare Blood Type
The Rh negative blood type is extremely rare. According to The Red Thread, only 16.6% of the population worldwide has Rh negative blood.
Pregnancy
An Rh negative pregnant woman’s immune system may make antibodies against Rh positive blood cells, including those of her unborn baby. This condition is called Rh sensitization. The Rh positive fetus that has been attacked by the mother’s immune system can become anemic, suffer congestive heart failure or even die. .
Genetics
According to Lisa Shea, genetics play a role in determining Rh factor. The only way a child can be Rh negative is if both parents are also Rh negative, because the negative factor is recessive.
References
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