It is possible to demonstrate an neurodegeneration in rats given doses of alcohol that produce blood-alcohol above .2 g /100ml for four hours. Alcohol can effect organogenesis early in pregnancy resulting in gross structural organ abnormalities before week 8 and after week 8 of pregnancy it can effect growth and CNS development. There are a large number of possible pathways that alcohol can alter to produce abnormalities including possible chromosome abnormalities, placenta dysmorphology, reduced fetal blood flow, and direct central nervous system effects influence neurodevelopment.

High Prenatal Doses of Ethanol Induce Neurodegeneration in Rats

The amount of neurodegeneration induced by ethanol is predicted by the time span during which the net dose is administered (not necessarily on the net dose alone) and on the duration of time during which the blood alcohol levels are elevated above the toxic threshold (defined here as 0.2 gm/100 ml). Seven-day old rats received subcutaneous injections at 2-hour intervals with varying amounts of ethanol and mean blood alcohol levels were calculated. Twenty-four hours after the first (or only) injection the rat brains were investigated for evidence of apoptosis. (Constructed from data in Ikonomidou, C. et al. Science, 287: 1056-1060, 2000) ©2008 NBEP
There is no safe period during pregnancy to drink alcohol.

Alcohol Effects the Fetus throughout Pregnancy

(Constructed from data in Agarwal, A.P. and Seitz, H.K. et al. Alcohol in Health and Disease, Ch. 15, 2001; Stratton, K. et al. Fetal Alcohol Syndrome Diagnosis, Epidemiology, Prevention, and Treatment, p. 37, 1996) ©2008 NBEP
There are many ways alcohol can cause abnormalities during pregnancy. This can account for the wide range of signs and symptoms seen in the FAS.

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(Constructed from data in Randall, C.L. et al. Alc Clin Exp Res, 14: 807 - 812, 1990 and Agarwal, D.P. and Seitz, H.K. et al. Alcohol in Health and Disease, Ch. 15, 2001) ©2008 NBEP