biochemical characteristics associated with the susceptibility to FAS. "Human gestation is divided into two major periods: the embryonic period (up to 8 weeks) and the fetal period (from 8 weeks to delivery). It's during the embryonic period that various drugs are introduced directly into the maternal bloodstream or administered through the maternal diet. Chemical/Physical agents that produce these fetal malformations are called teratogens. Most teratogens show selectivity towards certain organs, based on the timing of the embryo to the teratogen, the dosage taken, and the sensitivity of the dividing cells. Organs and limbs of the developing embryo are formed from collections of specialized cells. Exposure of an embryo to a teratogen during this period may have devastating effect on the formation of that organ." (Michaelis and Michaelis, p. 17) The primary metabolic product of alcohol is acetaldehyde which could also produce some damaging effects. The reasons that this is looked at, but not as directly as is alcohol, is because of the following reasons; Alcohol is distributed rapidly and nearly equally in maternal and fetal tissues, Alcohol applied directly onto embryos in vitro conditions in which no acetaldehyde is formed causes growth retardation. Because of this, these two mentioned factors are in effect causes indirectly, if not adversely directly, to the formation of the defects that are causes in the children of FAS. The nutritional aspect of FAS is not as simple. Normal growth and development during this priming period requires the transfer of a continuous supply of amino acids and glucose from mother to fetus. Several studies have shown that with the human placental tissue alcohol directly obstructs the transport of both these substances. These are two essential substances that, through research with rat embryos, have proven that the depravity of such causes malformations of fetal tissue's energy sources. The materials needed ...
