TOXICANT EXPOSURE AND TRACE-ELEMENT METABOLISM IN PREGNANCY

A review of the literature provides support for the concept that mater nal nutritional status has a significant influence on embryonic and fe tal development. The consumption of 'poor' diets has been shown to be a risk factor for poor pregnancy outcome, while the provision of selec ted nutritional supplements prior to and during pregnancy has been ass ociated with improved pregnancy outcome. Despite the above, it has bee n difficult to identify specific nutrient deficiencies as causative fa ctors of abnormal development. One explanation for this failure is tha t embryo/fetal nutritional deficiencies can arise through a number of mechanisms in addition to a low maternal intake of a nutrient(s). Evid ence is presented for the hypothesis that the developmental toxicity o f a number of teratogens can be ascribed, in part, to their ability to induce alterations in the partitioning of essential trace elements be tween the maternal and fetal unit. An implication of the above hypothe sis is that maternal diet can be an important modulator of the develop mental toxicity of several agents. (C) 1997 Elsevier Science B.V.