The biochemistry of prenatal alcohol exposure

In this contribution we review the biochemical pathways of ethanol and its metabolites in humans in the context of pregnancy. Special emphasis is devoted to the implications for fetal and neonatal development. The review covers primary direct effects of ethanol as well as downstream effector pathways involving modulation of receptor and hormonal signaling, and the enzymatic status of the offspring. Special attention is given to the implications of maternal alcohol consumption for the nutritional status of compounds with recognized relevance for pregnancies, such as folate, unsaturated fatty acids and zinc. The field of ethanol induced developmental disorders is enormous and still growing rapidly. Since pre-2000 material has been well covered by excellent review publications already, our manuscript concentrates on the more recent exciting developments in the field, like the interference of ethanol with neurosteroid and neuropeptide signaling. Accordingly, the references are biased heavily towards publications from the last decade. The emphasis is firmly on the biochemical pathways behind the manifestations of maternal alcohol in the neural development, physiological regulation and the immune competence of the fetus and the neonate. Extensive attention is given to the relatively new concept of in utero programming of fetal development. The epidemiological, social, or economic aspects of alcohol consumption during pregnancy are not covered by this review, as they are reviewed in other chapters of this volume