My husband had to have his blood checked way back then, when pregnant with our first child. It was because we didnt know his blood type and I am Resus negative. He is a negative too, so no probs there. I just got a phone call from docs office saying last bloods came back that I am aneamic. He is giving me until my 20week appoint to up my iron levels or I will have to go onto a supplement. I have been aneamic now with all three of my pregnancies. Its not a big deal but that is the reason they jab us with a needle so often.
I'm not too sure what they would want to see him for. I know low iron is common during pregnancy because your body makes so much more blood and baby takes it as well. I had it for awhile and it caused anemia. Its normally fixed by eating proper foods and and iron supplement on top of your prenatals. Your doctor will be able to explain everything if you ask em.