AbstractIn contrast to the well known effects of prenatal ethanol exposure on the central nervous system, data about its peripheral effects are scarce. Here, Sprague‐Dawley rats were fed a liquid diet (gestational days 0–20) containing 36% ethanol‐derived calories (EDCs, group H) or were pair‐fed with 18% EDCs (group L) or 0% EDCs (group C. On postnatal day 20, one male and one female from each of 10 litters per group were killed. Norepinephrine (NE) was analyzed in the frontal cortex, spleen and thymus, and dopamine, 5‐hydroxytryptamine (serotonin, 5‐HT) and their metabolites 3,4‐dihydroxyphenylacetic acid, homovanillic acid (HVA) and 5‐hydroxyindoleacetic acid (5‐HIAA) were analyzed in the striatum by high‐performance liquid chromatography with electrochemical detection. Lymphocyte subpopulations in the spleen and thymus were also assessed in half of these litters. Significant decreases in splenic NE concentration were seen in both sexes of group H (males 27%, females 28%). Decreases in striatal 5‐HT and 5‐HIAA of group H subjects appeared to be sex specific (only females were significantly affected: 23% decrease in 5‐HT, 37% decrease in 5‐HIAA). Pronounced, dose‐dependent reductions in T cell percentages were observed in both the thymus and spleen. Splenic CD8+and CD4+cell percentages were positively correlated with the splenic NE concentrations. It is concluded that the decreases seen in splenic T cell percentages subsequent to prenatal ethanol exposure may be caused, at least partially, by impaired noradrenergic control of this organ.