Neural tube defects are prevented by -

Ans. is 'b' i.e., Folic Acid Neural tube defect o Neural tube defects account for most congenital anamalies of the CNS. o It results from failure of neural tube to close spontaneously between the 3rd and 4th week of in utero development. o Lumbo-sacrol region is the most common site Etiology o NTDs have multiple etiological factors - Maternal diabetes Zinc and folate deficiency Maternal exposure to alcohol, radiation, valproate, carbamazepine Trisomy 13 and 15 o Maternal malnutrition is an impoant risk factor for development of NTD. There is decreased maternal folate levels in NTD affected pregnancies Periconceptional folic acid supplementation decreases the occurrence of NTD. Pathogenesis o The human nervous system develops from neuroectoderm. o During development, behind neuroectoderm lies the mesoderm that encloses the notochord which is derived from endoderm. o Veebral bodies develop from the mesoderm around the notochord. o Neuroectoderm forms invagination Neural groove. This neural groove separates from overlying surface ectoderm and becomes neural tube. o From developing veebral bodies, two dorsal projection extends, which grow around the neural tube and form veebral arch (pedicle and lamina). o Failure of these veebral arches to fuse give rise to Neural tube defect.