In regards to folic acid (also known as Vitamin B9) in the second and third trimesters of gestation, it is still an important nutrient for the development of the baby. It is ideal to build your levels of Folic acid in the preconceptive phase as well as the first trimester as this is the time when cellular division is most active. This process requires Folic acid for DNA and RNA (genetic material) synthesis, if the mother has a pre-existing deficiency of Folic acid complications during this fast growth phase can arise such as Spina bifida, neural tube defects or miscarriage.
Folic acid is also needed throughout the second and third trimester to ensure the structural integrity and constant growth of the developing baby. It is also required for the production of red blood cells. It is therefore still a good recommendation to continue taking it throughout your pregnancy to help ensure a healthy baby, nervous system and to also improve the general nutrition of the mother.