Not taking folic acid when you are pregnant does not necessarily have an effect. Folic acid belongs to the B vitamin class, which can prevent fetal neural tube disorders and should be taken from the preparation period to the second trimester of pregnancy. If you are already more than three months pregnant, you can see your doctor for an ultrasound examination and there is no abnormality in the morphology, which means that the fetus is not affected. Folic acid deficiency causes fetal abnormalities, which may include brain bulge and spina bifida, and can be seen on ultrasound. If you are deficient in folic acid yourself, you can take folic acid even after the third trimester of pregnancy under the guidance of your doctor. Folic acid also has a role in hematopoiesis, not only to prevent fetal neural tube disorders.