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.
The 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.
