Spina bifida, folic acid supplements

Prevention of fetal neural tube defect (spina bifida). Folic acid supplementation taken before conception and during the early weeks of pregnancy has been shown in an 8-year trial to prevent the condition in pregnancies subsequent to an affected birth. Women hoping to conceive and who have had an affected child are advised to take folic acid 5 mg/day. To prevent a first occurrence 400 micrograms/day should be taken both before conception, or as soon as possible after diagnosis. In both cases folate supplement should be taken for the first 12 weeks of pregnancy. 

Folic acid supplements are given to pregnant women to decrease the risk of neural tube defects such as spina bifida. Prenatal vitamin preparations that contain higher concentrations of folic acid must be dispensed under a health care worker s guidance because high folate intakes can mask the symptoms of pernicious anemia. 

Folic acid deficiency, unlike vitamin B12 deficiency, is often caused by inadequate dietary intake of folates. Patients with alcohol dependence and patients with liver disease can develop folic acid deficiency because of poor diet and diminished hepatic storage of folates. Pregnant women and patients with hemolytic anemia have increased folate requirements and may become folic acid-deficient, especially if their diets are marginal. Evidence implicates maternal folic acid deficiency in the occurrence of fetal neural tube defects, eg, spina bifida. (See Folic Acid Supplementation A Public Health Dilemma.) Patients with malabsorption syndromes also frequently develop folic acid deficiency. Patients who require renal dialysis develop folic acid deficiency because folates are removed from the plasma during the dialysis procedure. 

Neural tube defects, characterized by a failure of the neural tube to close properly after conception, affect about one in 1000 live births in the USA. Periconceptional folic acid supplementation reduces the risk. To determine whether periconceptional exposure to folic acid antagonists might therefore increase the risk of neural tube defects, data from a case-control study of birth defects (1979-98) in the USA and Canada have been examined (14). Data on 1242 infants with neural tube defects (spina bifida, anencephaly, and encephalo-cele) were compared with data from a control group of 6660 infants with malformations not related to vitamin supplementation. Triamterene is a folic acid antagonist and in this series was associated with the development of neural tube defects, but there were too few cases to estimate an odds ratio. 

The answer is a. (Murray, pp 812-828. Scriver, pp 3-45. Sack, pp 167-180. Wilson, pp 287-324.) Spina bifida is a defect of neural tube development that can be partially prevented by encouraging preconceptional folic acid supplementation in women desiring to become pregnant. Examination for subtle evidence of dysmorphology in children with major birth defects is necessary to rule out a syndrome. Syndromes often exhibit Mendelian or chromosomal inheritance. 

D. The fetus needs a constant supply of cofactors for normal development. Folic acid supplements of 400 pg/day prior to conception have been shown to decrease the incidence of neural tube defects such as spina bifida. 

Folic acid (vitamin Bg) is a conjugate of a pteridine unit, p-aminobenzoic acid, and glutamic acid. Deficiency of folic acid leads to anaemia, and it is also standard practice to provide supplementation during pregnancy to reduce the incidence of spina bifida. 

Folic acid is a vitamin (sometimes called vitamin M or vitamin Be) found naturally in mushrooms, spinach, and yeast. It is an important dietary supplement during pregnancy, as it reduces the likelihood of spina bifida. U.S. 5,968,788 (to Toray Industries) describes conditions for cultivating several strains of yeast or bacteria to increase their yield of folic acid, and gives yields for each species. Determine the optimum strain and recovery process to make a USE product and estimate the cost of production via this route. 

Spina bifida is one of a class of birth defects characterized by the incomplete or incorrect formation of the neural tube early in development. In the United States, the prevalence of neural-tube defects is approximately 1 case per 1000 births. A variety of studies have demonstrated that prevalence of neural-tube defects is reduced by as much as 70% when women take folic acid as a dietary supplement before and during the first trimester of pregnancy. One hypothesis is that more folate derivatives are needed for the synthesis of DNA precursors when cell division is frequent and substantial amounts of DNA must be synthesized. 

In the mid-twentieth century, pediatric care often began with a newborn examination shortly after birth. As of 2011, pediatric care often begins before conception. Women are advised via media sources or a health care provider to prepare for pregnancy and improve the chances for a healthy infant. This advice includes smoking cessation and supplementing the diet with folic acid, which decreases the incidence of neural tube defects, such as spina bifida. 

Neural tube defect Birth defects that involve an incomplete development of the brain and spinal cord, and their protective coverings. There are three types of neural tube defects anencephaly (underdeveloped brain), encephalocele (hole in the skull through which brain tissues protrude), and spina bifida (spinal column remains open). The supplementation of folic acid to women prior to conception and during the first month of pregnancy reduces the risk of neural tube defects. 

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