These 9 months, eat well for you and baby. The Mayo clinic specifically recommends Folic Acid, Calcium, Iron and general Prenatal Vitamins in this article here.
Of course good nutrition is not only limited to when you are pregnant. Stay up-to-date on your vitamin and nutrient knowledge with this cool interactive info-graphic from Information is Beautiful. Snake Oil? Scientific Evidence for Popular Health Supplements. (For more detail on their information sources, scroll to the bottom of the visualization and click on “find out more about this image.”)
Want to learn how to get specific nutrients from everyday foods? Check out these charts, which show minerals and vitamins broken out by food type.
As always, be sure to have the vitamins/nutrients discussion with your doctor.