What happens when you have a folic acid deficiency? Folic acid deficiency can also increase the risk of birth defects in pregnant women, including neural tube defects, which affect the brain and spinal cord of the developing fetus. In addition, folic acid deficiency may lead to elevated levels of homocysteine, an amino acid that is associated with an increased risk of cardiovascular disease. https://www.quora.com/What-happens-when-you-have-a-folic-acid-deficiency/answer/Vikash-Sharma-2756