How could my blood type affect my future child?

It won't. This will only be an issue if there is a question of paternity.
It doesn't . Blood type, by itself, won't cause problems with your child. If the mother has a negative rh factor (reported with the blood type e.g. B+ vs. B-) and the father is positive, that may cause an issue for the fetus but this is easily managed by the obstetrician with a simple medication. Certain genetic conditions you have or carry might affect your child though. Discuss with your doctors.

Related Questions

How could my spouses blood type affect my future child?

Jaundice. If you have type o or negative blood, and your spouse is different, your child could be born with type a or b, or rh pos blood. If that happens, there could be an antibody reaction at birth. However, hospitals test for that, and if it's noted there's a difference, they look for jaundice and treat it if seen. Truthfully, as it's caught early, it's not that big a deal anymore. Read more...