Medical Q&As

Rhesus factor - twins?

My twin sister recently found out she had rhesus negative blood. We are not identical twins but could this mean that I am rhesus negative also?

Since you are non identical twins it is possible for you both to have different blood groups. Your parentsí blood groups determine the various permutations of blood group that you could inherit. However, it is possible that you too could be rhesus negative. Approximately 15% of Caucasian people are rhesus negative. Your rhesus status assumes importance if you need to receive a blood transfusion. If you are rhesus negative you should only receive blood that is also rhesus negative otherwise a transfusion reaction could occur due to blood incompatibility. Also, if you are rhesus negative this could have implications for the future if you were pregnant with a child that was rhesus positive. I have already dealt with a query on this matter, which you can access through this link: