In order to assure normal fetal development, mother and fetus must both - at different times during gestation - contribute appropriate levels of thyroid hormone. If not, brain defects can result, some of which resemble those found in children suffering from fetal alcohol syndrome (FAS). Due to these commonalities, some researchers speculate that alcohol may mediate alcohol-related birth defects (ARBDs) by inducing hypothyroid conditions in utero. A study in the January issue of Alcoholism: Clinical & Experimental Research investigates if alcohol consumption during the equivalent of the third trimester in sheep results in an alteration of fetal or maternal thyroid function.
"The thyroid hormone system plays important roles in growth, development and in the function of other hormone and organ systems," explained Timothy A. Cudd, associate professor of physiology at Texas A&M University and lead author of the study. "Both mother and fetus must contribute thyroid hormone for normal fetal development. Early in development, before the fetus is capable of producing thyroid hormone, maternal thyroid hormone crosses the placenta to influence fetal development. Later in development, when higher concentrations are required for normal fetal development, a fetal contribution is required to create sufficient concentrations."
Cudd and his co-authors knew that brain abnormalities found in children who were exposed to abnormally low concentrations of thyroid hormone during fe