Birth defects
From The Nutritional Health Bible by Linda Lazarides (1997). This free database is provided for interest only. Linda's later writings refer to more up-to-date research.
Some causative factors (relating to the mother at the time of conception or early pregnancy)- Alcohol consumption
- Heavy metal toxicity
- Nutritional deficiencies (zinc, selenium, folic acid, essential fatty acids)
- Obesity.
Epidemiological and in vitro studies suggest a correlation between low selenium levels and a higher incidence of birth defects such as spina bifida. Zimmerman AW et al: Interaction between selenium and zinc in the pathogenesis of anencephaly and spina bifida. Z Kinderchir 44 Suppl 1:48-50, 1989.
Zinc deficiency is widespread and in pregnancy is associated with premature birth, inefficient labour and increased risk to the foetus. Growth impairment and lowered immunity occur in zinc-deficient children. Prasad AS: Zinc deficiency in women, infants and children. J Am Coll Nutr 15(2):113-20, 1996.
Low zinc levels frequently found in pregnant women constitutes a real risk of deficiency and consequent miscarriage, toxaemia, anaemia, prolonged gestation, difficult delivery, birth defects and learning disorders. Reviewing the literature, the authors conclude that zinc and multinutrient supplementation is imperative in pregnancy. Favier A et al: Effects of zinc deficiency in pregnancy on the mother and the newborn infant. Rev Fr Gynecol Obstet 85(1):13-27, 1990.
The use of multivitamins was compared between 731 mothers of babies born with a facial cleft or cleft lip or palate, and 734 mothers with non-malformed control babies. It was found that the use of multivitamins before and during pregnancy reduced the risk of offspring with this type of deformity by 25 to 50 per cent. Shaw GM et al: Risks of orofacial clefts in children born to women using multivitamins containing folic acid periconceptionally. Lancet 346(8972):393-6, 1995.
Zinc deficiency during pregnancy has been shown to be related to many congenital abnormalities of the nervous system in children, who may later develop reduced learning ability, apathy and mental retardation. Pfeiffer CC et al: Zinc, the brain and behaviour. Biol Psychiatry 17(3):513-32, 1982.
Mothers of 538 babies or foetuses with neural tube type birth defects (incomplete development of the brain or spinal cord) were compared with mothers of 539 non-malformed controls. It was found that the risk of occurrence of this type of birth defect was almost twice as great in obese mothers as in those of normal weight. Shaw GM et al: Risk of neural tube defect-affected pregnancies among obese women. JAMA 275(14):1093-6, 1996.
In a study of 513 pregnancies, the nutrient intakes of mothers of babies with dangerously low birthweights were found to be well below the nutrient intakes of mothers whose babies were in the safe range of birthweights. The mother's diet around the time of conception was more important than during pregnancy. The study also found that premature babies, and those of abnormally low birthweight were frequently born with deficiencies of the essential fatty acids required for brain development (arachidonic acid and DHA). Crawford MA et al: Nutrition and neurodevelopmental disorders. Nutr Health 9(2):81-97, 1993.
Promising nutritional researchThe risk of recurrent neural-tube defects (spina bifida and similar deformities) is decreased in women who take folic acid or multivitamins before and after the period of conception. Czeizel AE et al: Prevention of the first occurrence of neural-tube defects by periconceptional vitamin supplementation. N Engl J Med 327(26):1832-5, 1992
Daily zinc supplementation in women with relatively low plasma zinc concentrations in early pregnancy is associated with greater infant birth weights and head circumferences. Goldenberg RL et al: The effect of zinc supplementation of pregnancy outcome. JAMA 274(6):463-8, 1995
In 56 pregnant women at risk of delivering a small baby and supplemented with 22.5 mg zinc daily, the incidence of growth retardation was significantly reduced and health indices were better compared with controls. Simmer K et al: A double-blind trial of zinc supplementation in pregnancy. Eur J Clin Nutr 45(3):139-44, 1991.