FAS was recognised in 1973 as a consequence of chronic exposure to alcohol in the uterus. Since then many consequences of heavy drinking during pregnancy have been reported, including malformations, spontaneous abortion and decreased birth weight. However, the effects of moderate drinking, defined as less than two drinks per day, on foetal malformations, remained unclear. The aim of this research was to determine if there is an association between moderate drinking in the first three months of pregnancy and a higher risk of foetal malformations.

Extensive literature search

The study used data bases to carry out a literature search for (1) pregnant women, (2) moderate alcohol use (more than two drinks a week to two drinks per day), (3) case-control or cohort study, (4) inclusion of an abstainer group, (5) major or minor malformations included in the outcome measures, and (6) report in English. Studies in which moderate alcohol use could not be confirmed were excluded, together with case reports and editorials. The Methods section of each study was examined independently by two blinded investigators, with a third one settling any disagreements. Of the 24 studies that met the inclusion criteria, only seven had extractable data (one case-control study and six cohort studies). Together, these seven studies had evaluated 130,810 pregnancy outcomes, with 24,007 among moderate drinkers and 106,803 among abstainers. An overall odds ratio showed that the relative risk of foetal malformations was 1.01. There was no relationship between the quality of the studies and whether they found a positive or negative association with alcohol consumption and foetal malformation.

Women should not be misinformed

Moderate drinking during the first three months of pregnancy is not associated with a greater risk of foetal malformations. Women drinking in moderation (2-14 drinks weekly) before finding out they have conceived should not be misinformed to believe that they run a greater than normal risk of giving birth to a child with FAS. Such information may lead many of them to consider termination of an otherwise wanted pregnancy.