There is no doubt as to the teratogenic potential of high levels of alcohol. The effects on children of exposure to lower doses than those triggering foetal alcoholisation syndrome are less well understood. Women of child-bearing age consume less alcohol than men. When they are pregnant, most women reduce their alcohol consumption, generally as from the first trimester of pregnancy. In the perinatal survey conducted in 1995 in all French maternity hospitals (representative sample), 5 % of the women interviewed at the hospital declared that they drank at least one glass of alcohol per day during their pregnancy; in 1998, this percentage was 3.9 %. Similarly, a study carried out at the Roubaix Maternity Hospital confirmed a lower declared consumption rate in pregnant women: 15 % of the women drank at least 2 glasses per day in 1985-1986, compared with 10 % in 1990-1991 and 4 % in 1992.
Excessive alcohol consumption affects female fertility. In men and women, moderate alcohol intake is not associated with reduced fertility. An increased perinatal mortality or prematurity has been observed in certain studies in cases where about two glasses/day were consumed but the confounding factors are not always checked. The birth weight is, on average, lower for children exposed in utero to average or high alcohol levels. The results are less marked for lower exposures (less than 2 glasses per day), some studies showing differences for the consumption of one glass/day and others not observing any effect under the consumption of 3 or 4 glasses/day. Therefore, no threshold under which there would be no impact on birth weight has been established.
Follow-up studies have been carried out to monitor children exposed to variable alcohol consumption during pregnancy: the children underwent a psychomotor development or IQ (intellectual quotient) test as babies or young children. Some of these studies have shown that children exposed to more moderate levels of alcohol during pregnancy than children affected by FAS have intellectual deficits or behavioural disorders similar, albeit less marked, to those presenting with FAS. A reduction in IQ of the order of 5 to 7 points in children of pre-school or school age has been detected in cases where maternal alcohol consumption was more than or equal to 2 to 3 glasses/day. One of the studies that monitored children up until 14 years of age, demonstrated the effects of such consumption during pregnancy on memory and arithmetic skills and on the children’s reading ability. A threshold effect on cognitive functions corresponding to the consumption of 2 to 3 glasses/day cannot, however, be deduced. For lower rates of consumption, only studies involving a very large number of subjects could establish the presence or absence of any effects. Excessive one-time consumption (at least 5 glasses at one time) during pregnancy has also been linked with intellectual deficits in children. Epidemiological studies thus confirm the harmful effects on birth weight and on cognitive functions in children of the consumption of 2 glasses/day, some studies having demonstrated a dose-effect relationship. It should be remembered that, from the results obtained in experimental studies, it is not possible to confirm a dosing threshold under which maternal alcohol consumption during pregnancy has no risk to the offspring.