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People with type O blood are 37% less likely to get pancreatic cancer than all other blood types. Again, a reaction to H. pylori may be responsible. This is great news for people with Type O blood, but not so much for everyone else.
Type O Blood Might Increase Your Chances Of Getting An Ulcer
Having type O blood can increase your risk of developing an ulcer. While ulcers aren’t exactly fun, it’s not as bad as it could be. The bacteria that causes ulcers, H. pylori, may also be responsible for the increased risk of gastric cancer in people with other blood types. Most people would prefer the ulcer.
Why the difference? Because your blood type influences how your immune system responds to threats.
Your Rh Factor Can Cause Problems During Pregnancy
Just like people have different blood types, they can also differ in their Rh factor. The Rh factor is a protein that can exist on the surface of red blood cells. Rh+ people have this protein, and Rh- people, who are far less common, do not.
While a person’s Rh factor doesn’t usually make much difference, it can become a problem during pregnancy. If a pregnant person is Rh-, and the fetus is Rh+, the incompatibility can be dangerous. Why? Because an Rh- person’s immune system might make antibodies against the Rh factor. While the pregnant person’s blood system is separate from the fetus’, traces of blood can still cross over through the placenta. This can lead to those antibodies attacking the fetus’ Rh factor. This can cause hemolytic anemia, a condition where blood cells are wiped out faster than the fetus can rebuild them, and it can be fatal.
This problem typically doesn’t occur during the first pregnancy, because the pregnant person’s immune system hasn’t built up enough antibodies yet, but it is a risk for subsequent pregnancies. To prevent this, Rh- people can take an injection of Rh immunoglobulin (RhIg), which stops the production of Rh antibodies.