Researchers gave pregnant ewes alcohol doses of 0.75, 1.25, 1.5 or 1.75 g/kg or saline through catheters beginning on day 109 of gestation (a full term for sheep is 145 days). The ewes received alcohol or saline on three consecutive days, followed by four days without exposure, thereby mimicking a pattern of binge drinking. Fetal and maternal blood samples were collected on days 118 or 132.
"The administration of alcohol to sheep during the equivalent of the third trimester of pregnancy resulted in altered thyroid function in both the mother and fetus," said Cudd.
"This is an important study because even today so little is known regarding the mechanisms through which alcohol intake by pregnant mothers is bad for their fetuses," said Catherine Rivier, a professor of neuroendocrinology/neurosciences at The Salk Institute. "In addition, the sheep is a good model for the human because the thyroid system of both species develops similarly during gestation. Prior to this study, we knew that, in general, fetal brain development requires thyroid hormones to grow normally and build all the right connections. We knew that children born to mothers who have low thyroid hormone levels are often retarded. These results show us that alcohol given to a