Prenatal ethanol exposure in C57 mice: effects on pregnancy and offspring development.

Pregnant mice were fed lab chow or isocaloric liquid diets containing different concentrations of ethanol or sucrose from Day 5 through Day 17 of gestation. Ethanol added to the diet reduced ad lib consumption compared to that of the diet with sucrose. The reduced consumption was accompanied by an attenuated weight gain during pregnancy. The attenuated weight gain, however, was not specific to alcohol as evidenced by an equivalent attenuation for sucrose controls pair-fed to the ethanol group. Prenatal ethanol exposure increased neonatal mortality which appeared to be unrelated to the prenatal attenuated weight gain or to postnatal nurturance. Surviving offspring, reared by their biological mothers, had body weights similar to controls at birth and during lactation. However, in contrast to previous reports, mice prenatally exposed to ethanol manifested weight reductions near weaning that extended into adulthood (60 days). In spite of the increased mortality and reduced body weight, motor activity assessed by either longitudinal or cross-sectional methods was not influenced by the treatments. Possible mechanisms for the delayed weight reduction include retarded maturation and/or dysfunction of neural systems involving food regulation.