A couple of other vitamins that help are
vitamin E, C, and of course folic acid.
Vitamin E has been shown to increase sperm count dramaticly, and vitamin C for both men and women helps the sperm and eggs develop to their full potential. Folic acid helps prevent miscarriages and birth defects. Right now I am taking Prenatel, folic acid, vitamins C and E, chaste tree berry extract, and zinc along with Metformin as directed by my doctor.