Fetal Alcohol Syndrome and Maternal Alcohol Biomarkers in Sera: A Register-Based Case-Control Study.

Background: Fetal alcohol syndrome (FAS) is a well-known consequence of prenatal alcohol exposure. However, women tend to deny or underreport their alcohol use during pregnancy. The aim of this study was to explore the usability of various alcohol biomarkers for FAS screening in a data set without information on self-reported alcohol use.

Methods: A nationwide register study with a case-control design was conducted. The target population consisted of all live births in Finland from 1987 to 2005. FAS cases (n = 565) were identified from the Finnish Register of Congenital Malformations. Mothers of FAS cases and their controls were selected in a ratio of 1 to 2 from the Finnish Maternity Cohort (FMC). Background information was obtained from the Finnish Medical Birth Register. Serum samples, collected at the mother's first visit to the maternity care, were obtained from the national FMC biobank. Biomarkers of alcohol consumption, gamma-glutamyltransferase (GGT), carbohydrate-deficient transferrin (%CDT), combination of GGT and CDT (GGT-CDT), and ethylglucuronide (EtG) were analyzed from mothers of FAS cases (n = 385) and their controls (n = 745).

Results: Median levels of all biomarkers were significantly higher among the mothers of FAS children than in control mothers. Using previously validated cutoffs for EtG, GGT, %CDT, and GGT-CDT, nearly half (46%) of the mothers with affected offspring could be identified. The predictive association was highest for GGT-CDT combination and significant also for all the other biomarkers.

Conclusions: In this explorative case-control study, we demonstrate that the FMC biobank can be used to screen alcohol biomarkers for epidemiological research purposes. According to our results, the use of alcohol biomarkers during the first trimester may help to identify the high-risk pregnancies for FAS. A more systematic use of alcohol biomarkers at maternity care may open new possibilities for screening and intervention of alcohol use among pregnant mothers.