So you're starting a family.
I truly hope you will give the child growing within you the best chance possible.
Some things to consider about giving your baby the best chances are:
Eating a nutritious diet, even before you're pregnant,
especially in relation to folic acid.
Water contains no caffeine or fat so is a great choice.
Abstaining from illegal drugs and alcohol while pregnant.
Both drugs and alcohol can cause serious and irreparable damage.
Ensuring any prescribed drugs you're taking will not affect a fetus. Check with your doctor about any possible side effects.
Abstaining from foods that can be contaminated e.g.: raw fish, raw eggs, unwashed vegetables, some soft cheeses
Loving your partner and ensuring your relationship is strong.