Maternal alcohol consumption and spontaneous abortion.

This review examines the relationship between maternal alcohol consumption during pregnancy and spontaneous abortions. Although very high spontaneous abortion rates have been reported for alcoholic women, it is still uncertain if this is due to the direct effects of alcohol or the indirect effects of alcoholism-related disorders such as cirrhosis. The higher rates of spontaneous abortion among alcoholics may also be due to their higher pregnancy rates. Studies in animals indicate that blood alcohol levels > 200 mg/dl can directly precipitate spontaneous abortion. The association between lower levels of maternal alcohol consumption and spontaneous abortion is much less clear. There is a definite effect of study site in these latter studies: those conducted in North America nearly always report statistically significant associations; those conducted in Europe or Australia nearly always report no significant associations. The reason for this difference is not related to differences in alcohol consumption. Possible explanations for this geographical difference include difference in the socioeconomic status of the women being studied and artefacts associated with the designs used to study these relationships.