You should be taking some sort of pregnancy vitamins. Your baby steals all your vitamins & leaves you nothing. Also, your baby needs extra calcium, iron, folate & all sorts of things. If I were you I'd take them. I did with my 3 & do does everyone I know.
Just make sure you are eating a balanced diet. The prenatal vitamins made me sick when I was first pregnant. I didn't take them until I was around 4 months. Folic acid is very important during pregnancy. Make sure to eat leafy greens, beans, citrus, tomato juice, lentils.
Yes. You should have begun prenate vitamins as siin as you found out you were pregnant. Deficiencies in certain vitamins and minerals have been directly linked to physical and mental defects babies. Folic Acid is the main one. VERY important for proper fetal development. You should have taken this BEFORE your first trimester which is a critical time in fetal development. These days most people in western countries are very defient in many of the vitamins a minerals needed for good health and being pregnant increases that defiency because your body is providing for both you and the child. Prenate supplements are very very important.