I just responded to someone else with a similar question. I'm a chimera and I contain both universal donor and universal recipient blood types. It was discovered when I was doing some testing for government work. I've had a son with B pos and a daughter with A neg, and twins with A pos. The latter gave me a bone marrow transplant with their placental stem cells curing a cancer I had at the time.
My situation aside. Most people know of ABO blood typing and RH factor. There is more than one blood typing method and some list far more blood types than ABO and RH factor. There is in common ABO blood typing an RH neutral which still gets marked negative or positive. I forget what the criteria for it is. But people with it can have children that seem to have incompatible RH factors.
Your unlikely to be in the same situation I am with my blood and tissue type. But here is the interference factor chart for common typing. Just click on RH or blood type to see the lists.
You do need to specifically ask the doctor to request a blood typing. They do not randomly do this on just any blood requisition. I went through this many times, also forgetting to ask, but you do need to ask for your typology for them to determine it.
I hope this helps.
Good luck, and if you have any other questions that I can help you with, please feel free to message me directly.
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