High dose alcohol consumption during pregnancy increases the risk for a plethora of adverse offspring outcomes. Both clinical and pre-clinical studies have demonstrated prenatal alcohol exposure can contribute to offspring with neurodevelopmental, cognitive and social deficits, as well as psychiatric illnesses, such as depression and anxiety. However, much less evidence is available on the effects of low dose and alcohol exposure in early pregnancy on mental health outcomes. This is critically important as many women have unplanned pregnancies and are consuming alcohol prior to pregnancy recognition.
We have developed a rodent model of moderate prenatal alcohol exposure that is confined to time around conception. Both male and female offspring exposed to this ‘periconceptional’ alcohol (PC:EtOH) developed altered neuroendocrine function and behaviour. PC:EtOH exposure resulted in a significant increase in depressive- and anxiety-like behaviours as well as altered social phenotypes. Interestingly, PC:EtOH exposure reduced basal plasma corticosterone concentrations in female but not male offspring. In early life, there was no impact of PC:EtOH on plasma corticosterone responsiveness however, in aged offspring, stress-induced plasma corticosterone and the pressor response to restraint were significantly reduced in female offspring. Adrenal and hypothalamic mRNA expression of genes regulating glucocorticoid production were not overtly altered by PC:EtOH. However, aged female offspring exposed to PC:EtOH, demonstrated increased expression of the glucocorticoids receptor in the hippocampus, suggesting altered hypothalmic-pitutary-adrenal (HPA) regulatory pathways.
This study supports the hypothesis that alcohol exposure even prior to implantation programs sex-specific alterations in offspring in a rodent model. Effects of alcohol on the maternal HPA and related physiological changes as a consequence of PC:EtOH are likely to underlie behavioural outcomes observed in this study. This research highlights the importance of public health messaging recommending abstinence from alcohol as part of preconception planning.