[1] Y. I. Goh and G. Koren. Folic acid in pregnancy and fetal outcomes. J. Obstet. Gynaecol, 28(1):3-13, 2008.
[2] A. Hisam, M. Rahman, and S. F. Mashhadi. Knowledge, attitude and practice regarding folic acid deficiency; a hidden hunger. Pakistan J. Med. Sci., 30(3):583-588, 2014.
[3] R. C. Folic acid. in modern nutrition in health and disease. 10th ed. Lippincott Williams Wilkins, Balt., pages 470-481, 2006.
[4] L. Mahmood. The metabolic processes of folic acid and Vitamin B12 deficiency. J. Heal. Res. Rev., 1(1):5-9, 2014.
[5] H. Gupta and P. Gupta. Neural Tube Defects and Folic Acid Hema Gupta. Indian Pediatr, 41:577-586, 2004.
[6] V. Saxena, M. Naithani, R. Kumari, R. Singh, and P. Das. Peri-conceptional supplementation of folic acidknowledge and practices of pregnant women and health
providers. J. Fam. Med. Prim. care, 5(2):387-392, 2016.
[7] K. S. Au, A. Ashley-Koch, and H. Northrup. Epidemiologic and genetic aspects of spina bifida and other neural tube defects. Dev. Disabil. Res. Rev., 16(1):6-15, 2010.
[8] A. E. Czeizel, M. Dob´o, and P. Vargha. Hungarian cohort-controlled trial of periconceptional multivitamin supplementation shows a reduction in certain congenital abnormalities. Birth Defects Res. Part A Clin. Mol. Teratol, 70(11):853-861, 2004.
[9] R. D. Wilson, G. Davies, V. D´esilets, G. J. Reid, A. Summers, P. Wyatt, and D. Young. The use of folic acid for the prevention of neural tube defects and other congenital anomalies. J. Obstet. Gynaecol. Can., 25(11):959-965, 2003.
[10] M. Gadgil1, K. Joshi, A. Pandit, S. Otiv, R. Joshi, J. T. Brenna, and B. Patwardhan. Imbalance of folic acid and vitamin b12 is associated with birth outcome: an indian
pregnant women study. Eur. J. Clin. Nutr., 68:726-729, 2014.
[11] R. J. Schmidt, S. Ozonoff, R. L. Hansen, J. Hartiala, D. J. Tancredi, H. Allayee, and et al. Maternal periconceptional folic acid intake and risk of autism spectrum disorders and developmental delay in the charge (childhood autism risks from genetics and environment) casecontrol study. Am. J. Clin. Nutr., 96(1):80-89, 2012.
[12] S. J. James, M. Pogribna, I. P. Pogribny, S. Melnyk, R. J. Hine, J. B. Gibson, and et al. Abnormal folate metabolism and mutation in the methylenetetrahydrofolate reductase gene may be maternal risk factors for down syndrome. Am. J. Clin. Nutr., 70(4):495-501, 1999.
[13] E. F. M. Reynolcts. The extra pharmacopoeia. London : Royal Pharmaceutical Society, 31st ed. / edited by james e.f. reynolds edition, 1996.
[14] C. Bower, H. D’Antoine, and F. J. Stanley. Neural tube defects in australia: Trends in encephaloceles and other neural tube defects before and after promotion of folic acid supplementation and voluntary food fortification. Birth Defects Res. Part A Clin. Mol. Teratol, 85(4):269-273, 2009.
[15] R. J. Berry, Z. Li, J. D. Erickson, S. Li, C. A. Moore, H. Wang, and et al. Prevention of neural-tube defects with folic acid in china. N. Engl. J. Med., 341(20):1485-1490, 1999.
[16] M. J. Berg. The importance of folic acid. J. Gend. Specif. Med., 2(3):24-28, 1999.
[17] L. Zhu, R. J. Berry, L. Song, and et al. Preventive effects of folic acid alone on neural tube defects in Chinese women before and after pregnancy. Ch. J. of Surgery,
80(7):493-498, 2000.
[18] L. M. De-Regil, J. P. Pe~na Rosas, A. C. Fern´andezGaxiola, and P. Rayco-Solon. Effects and safety of periconceptional oral folate supplementation for preventing birth defects. Cochrane database Syst. Rev., (12), 2015.
[19] H. Al-Hossani, H. Abouzeid, M. M. Salah, H. M. Farag, and E. Fawzy. Knowledge and practices of pregnant women about folic acid in pregnancy in abu dhabi, united
arab emirates. East. Mediterr. Health J., 16(4), 2010.
[20] S. B. Nosrat, M. Sedehi, and M. J. Golalipour. Knowledge and practice of urban iranian pregnant women towards folic acid intake for neural tube defect prevention. J. Pak. Med. Assoc., 62(8):785-789, 2012.
[21] A. A. Al-Akhfash, A. M. Abdulla, A. M. Osman, J. I. Abdulgafar, and A. A. Almesned. Maternal knowledge and use of folic acid among saudi females. Saudi Med.
J., 34(11):1173-1178, 2013.
[22] A. Benera, M. G. A. Al Maadidb, D. A. E. Al-Bastb, and S Al-Marric. Maternal knowledge, attitude and practice on folic acid intake among arabian qatari women. Reprod. Toxicol., 21(1):21-25, 2006.
[23] S. E. VOLLSET and B. LANDE. Knowledge and attitudes of folate, and use of dietary supplements among women of reproductive age in norway 1998. Acta Obstet.
Gynecol. Scand., 79(6):513-519, 2000.
[24] S. A. Knowledge, attitude and behavior concerning folic acid among women in child bearing age. Front. fetal Heal, 2(9-11):1-76, 2000.
[25] K. Nawapun and V. Phupong. Awareness of the benefits of folic acid and prevalence of the use of folic acid supplements to prevent neural tube defects among thai women. Arch. Gynecol. Obstet., 276(1):53-57, 2007.
[26] K. Deepti, H. Anila, C. Arup, and B. Vinohar. Determinants of knowledge regarding folic acid in periconceptional use among pregnant mothers in southern india. J. Den. Med. Sci., 4(3):25-29, 2013.
[27] M. R. French, S. I. Barr, and R. Levy-Milne. Folate intakes and awareness of folate to prevent neural tube defects: A survey of women living in vancouver, canada. J. Am. Diet. Assoc., 103(2):181-185, 2003.
[28] A. Ren, L. Zhang, Z. Li, L. Hao, Y. Tian, and Z. Li. Awareness and use of folic acid, and blood folate concentrations among pregnant women in northern chinaan area with a high prevalence of neural tube defects. Reprod. Toxicol., 22(3):431-436, 2006.
[29] M. A. Canfield, S. M. Przybyla, A. P. Case, T. Ramadhani, L. Suarez, and J. Dyer. Folic acid awareness and supplementation among texas women of childbearing age. Prev. Med. (Baltim), 43(1):27-30, 2006.
[30] S. Sen, A. Manzoor, M. Deviasumathy, and C. Newton. Maternal knowledge, attitude and practice regarding folic acid intake during the periconceptional period.
Public Health Nutr., 4(4):909-912, 2001.
[31] H. Riazi, S. Bashirian, and L. Amini. Awareness of pregnant women about folic acid supplementation in iran. journal of family and reproductive health, 6(4):159-163, 2012.
[32] M. Rehan, N. Mahmood, and S. B. Mazhar. Knowledge, attitude and practices regarding periconceptional folic acid supplementation in a tertiary care hospital. Ann.
Int. Med. Dent. Res., 11(4):172-175, 2015.
[33] L. Jaber, I. A. Karim, Jawdat A. M., M. Fausi, and P. Merlob. Awareness of folic acid for prevention of neural tube defects in a community with high prevalence of consanguineous marriages. Ann. Genet., 47(1):69-75, 2004.
)
