Female Wistar rats were given ethanol in their drinking fluid to cover 20-25% of the total calories consumed for 3-4 weeks prior to, during and also after pregnancy in some experiments. Soya oil was substituted for ethanol isocalorically in the control groups. Apart from a statistically significant reduction in litter size based on the number of apparent normal foetuses at intrauterine examination, no significant changes in reproductive performance could be recorded after ethanol treatment. In the offspring, examined up to 24 days of age, the body and some viscera weights were statistically significantly higher at some stages from 2 to 14 days. The general trend, however, showed that there were no significant differences in body, brain, liver, kidney, and heart muscle weights between control and ethanol offspring measured in rats between 0 and 24 days of age. Two gross malformations were recorded among 321 pups of ethanol treated mothers, whereas no malformations were found in 444 control pups. It was concluded that moderate ethanol consumption by rat mothers for 3-4 weeks before and during pregnancy as well as during the suckling period, had no serious effects on their reproductive performance and the development of their offspring measured by the parameters used in the present investigation.