References
- Rengasamy Padmanabhan. Etiology, pathogenesis and prevention of neural tube defects. Congenit anom 2006;46:55–67.
- Frey L, Hauser WA. Epidemiology of neural tube defects. Epilepsia 2003;44:4–13.
- MRC Vitamin Study Research Group. Prevention of neural tube defects: result of the medical research council vitamin study. Lancet 1991;338:131–137.
- Creizel AE, Dudas I. Prevention of the first occurence of neural tube defects by periconceptional vitamin supplemantation. N Engl J Med 1992;327:1832–1835.
- Beaudin AE, Stover PJ. Insights into metabolic mechanisms underlying folate-responsive neural tube defects: a minireview. Birth Defects Res 2009;85:274–284.
- Kirke PN, Molloy AM, Daly LE, Burke H, Weir DG, Scott JM. Maternal plasma folate and vitamin B12 are independent risk factors for neural tube defects. Q J Med 1993;86:703–708.
- Wald NJ, Hackshaw AD, Stone R, Sourial NA. Blood folic acid and vitamin B12 in relation to neural tube defects. Br J Obstet Gynaecol 1996;103:319–324.
- Groenen PM, Van Rooij IA, Peer PG, Gooskens RH, Zielhuis GA, Steegers-Theunissen RP. Marginal maternal vitamin B12 status increases the risk of offspring with spina bifida. Am J Obstet Gynecol 2004;191:11–17.
- Ray JG, Blom HJ. Vitamin B12 insufficiency and the risk of fetal neural tube defects. Q J Med 2003;96:289–295.
- Ray JG, Wyatt PR, Thompson MD, Vermeulen MJ, Meier C, Wong PY, Farrell SA, Cole DE. Vitamin B12 and the risk of neural tube defects in a folic-acid – fortified population. Epidemiology 2007;18:362–366.
- Henk J. Folic acid, methylation and neural tube closure in humans. Birth Defects Res 2009;85:295–302.
- Savage DG, Lindebaum J, Stabler SP, Allen R.H. Sensitivity of serum methylmalonic acid and total homocysteine determinations for diagnosing of cobalamin and folate deficiency. Am J Med 1994;96:239–246.
- Lindenbaum J, Savage DG, Stabler SP, Allen RH. Diagnosis of cobalamin deficiency: relative sensitivities of serum cobalamin. Methylmalonic acid, and total homocysteine concentrations. Am J Hem 1990;34:99–107.
- Scott JM, Weir DG. The methyl folate trap. Lancet 1981;2:337–340.
- Milman N, Byg K-E, Bergholt T, Eriksen L, Hvas A-M. Cobalamin status during normal pregnancy and postpartum: a longitudinal study comprising 406 Danish women. Eur J Haematol 2006;76:521–525.
- Walker M.C, Smith G.N, Perkins S.L, Keeley E.J, Garner P.K. Changes in hemocysteine levels during normal pregnancy. Am J Obstet Gynecol 1999;180:660–664.
- Steegers-Theunissen RP, Boers GH, Trijbels FJ, Finkelstein JD, Blom HJ, Thomas CM, Borm GF, Wouters MG, Eskes TK. Maternal hyperhomocysteinemia: a risk factor for neural-tube defects? Metabolism 1994;43:1475–1480.
- Mills JM, McPortlin JM, Kirke PN, Lee YL, Conley MR, Weir DG, Scott JM. Homocysteine metabolism in pregnancies complicated by neural-tube defects. Lancet 1995;145:149–151.
- Steen MT, Boddie AM, Fisher AJ, Macmahon W, Saxe D, Sullivan KM, Dembure PP, Elsas LJ. Neural-tube defects are associated with low concentrations of cobalamin (vitamin B12) in amniotic fluid. Prenat Diagn 1998;18:545–555.
- Steegers-Theunissen RP, Steegers EA, de Boer R, Thomas CM, Kloosterman MD, Eskes TK. Elevated folate levels in amniotic fluid after oral supplementation. Eur J Obstet Gynecol Reprod Biol 1990;36: 283–291.
- Zittoun J, Zittoun R. Modern clinical testing strategies in cobalamin and folate deficiency. Semin Hematol 1999;36:35–46.
- Mcmullin MF, Young PB, Bailie KEM, Savages GA, Lappın TRJ, White R. Homocysteine and methylmalonic acid as indicators of folate and vitamin B12 defifiency in pregnancy. Clin Lab Haem 2001;23:161–165.
- Briddon A. Homocysteine in the context of cobalamin metabolism and deficiency states. Amino Acids 2003;24:1–12.
- Patel N, Briddon A. Moderately low vitamin B12 does not compromise transmethylation in adults on a free diet: implications for assessment of B12 status. Ann Clin Biochem 2000;37:686–689.
- Hoey H, Linnell JC, Oberholzer VG, Laurance BM. Vitamin B12 deficiency in a breastfed infant of a mother with pernicious anaemia. J Roy Soc Med 1982;75:656–658.
- Steegers-Theunissen RP, Van Iersel CA, Peer PG, Nelen WL, Steegers EA. Hyperhomocysteinemia, pregnancy complications, and the timing of investigation. Obstet Gynecol 2004;104:336–343.