Reply to Ceccanti et al.

To the Editor:

Prenatal exposure to alcohol may cause a large spectrum of congenital anomalies, usually called fetal alcohol spectrum disorder or FASD. The key features of FASD are a characteristic pattern of facial anomalies and growth and developmental retardation, but a large number of other congenital defects have been described in children with FASD (Autti-Ramo et al., 2006; Hoyme et al., 2005). Our article reported a possible association between congenital diaphragmatic hernia (CDH) and FASD (Felix et al., 2008). In their letter, Drs. Ceccanti, Cozzi, and Ceccanti raise two important issues, concerning the craniofacial phenotype of our cases and the assessment of maternal alcohol consumption.

The specific craniofacial features seen in FASD include short palpebral fissures, thin vermillion border of the upper lip, smooth philtrum, epicanthal folds, anteverted nares, and midfacial hypoplasia (Autti-Ramo et al., 2006). None of the 40 cases of CDH in our study that were prenatally exposed to alcohol displayed this typical or even a related craniofacial phenotype.

Maternal alcohol consumption was assessed by a self-administered questionnaire, which included two questions related to prenatal alcohol exposure. The first question, of which the results were described in our article, related to the frequency of alcohol consumption during the period from 1 month before conception to the end of the third month of pregnancy. The answers to this question showed a highly significant association between maternal use of any alcohol during this period and CDH. We found a slightly higher risk for mothers with the most frequent consumption, but CIs overlapped. The second question pertained to the number of times that the mother drank five or more alcoholic beverages on one occasion during the same period. The results from this question were not described in our article, as the numbers were very small. Of the 40 case mothers with exposure to alcohol, 34 never had five or more drinks at a time during this period, five reported drinking that amount on one to three occasions, and one case mother answered she drank that amount once to four times per week. Our questionnaire did not give us further information about the type of alcoholic beverage and alcohol intake during the second and third trimester, as we focused our questioning on the trimester during which most of the organogenesis occurs.

A more detailed assessment of maternal alcohol intake could shed more light on the possible association between maternal alcohol consumption and the development of CDH and whether this association is dose-dependent. Therefore, we endorse the view of Ceccanti et al. that further, more specific studies on this subject are needed.