I’m RHneg, and when I had both my babies (at Wanfang Hospital), the doctor made a special note to prepare what I needed, closer to the birth. If my memory serves me correctly, my doctor told me they work with Renai hospital to make sure they have the blood needed, but reassured me the risk of needing a transfusion was extremely low. What they did have to get in for me was the shot RHneg mothers have after the first birth/miscarriage/aborted pregnancy, or if there are signs of bleeding. (pickawit will give the the proper terms for all this, I am sure ) Hospitals generally don’t carry this shot and they need to order it in, and my doctor asked me to remind him. Hospitals in the west used to give a shot at so many months into pregnancy as routine but no longer do it, and my doctor didn’t do it either, but recommended the one after giving birth.
Hope that helps and doesn’t confuse you more!
(I am registered as a blood donor here and have been called to donate once where they needed RH neg blood.)