It can effect health of baby if you were RH negative and your baby's father was RH positive. Something along them lines I remember asking the same thing a few weeks back
People with different blood types have proteins specific to that blood type on the surfaces of their red blood cells. If you are RH positive you have the protein on the surface of your blood cells if you are RH negative you don't. Most people are RH positive.
Never mind !!! Ignore this post.. It means negative lol sorry