The Rh Negative Blog

Blood type dating works similar to looking at the man as the blood donor and the woman as the receiver of his blood

In other words: It is about compatibility. If a man can donate blood to you, then your offspring with him will be neither Rh nor ABO incompatible.

Remember:

Maternal and fetal blood incompatibility (mother with negative Rh blood and fetus with positive Rh blood) increased the likelihood of being born with disabilities.