Ethyl glucuronide in maternal hair to objectively assess alcohol consumption in the three trimesters of pregnancy

Background. Prenatal alcohol exposure (PAE) creates a significant risk for child neurodevelopment, but reliable epidemiological data on PAE are missing. The main objective of the study was to assess the prevalence and amount of alcohol consumption in the three trimesters of pregnancy on the basis of ethyl glucuronide (EtG) testing in maternal hair.

Methods. Data collected from postpartum women (n=150) who give birth in the Institute of Mother and Child (Warsaw, Poland) included hair samples, self-reports of health related behaviors before and during pregnancy (i.e. alcohol use) and socio-demographic characteristics, supplemented by gynecological and neonatological data. Hair specimens of 135 participants were divided into three segments corresponding to the three trimesters of pregnancy while in 15 cases hair were analyzed for the entire 9 moths. EtG was measured by gas chromatography tandem mass spectrometry method in the Analytical Pharmacotoxicology Unit of National Institute of Health (Rome, Italy). Society of Hair testing EtG cut-offs were considered to characterize drinking behavior during pregnancy.

Results. Standard medical interview revealed no cases of alcohol use during pregnancy. When interviewed by the project staff any alcohol use after conception but before learning about being pregnant was reported by 32% and any alcohol use during the conscious pregnancy – by 3,4% participants. The analysis of EtG concentration in maternal hair indicated 50,3% women who had been drinking alcohol at any time during pregnancy, including 10% with excessive alcohol consumption in any trimester. Most participants maintained the same level of alcohol consumption throughout the pregnancy: 49,3% - abstinence; 18,6% - social drinking and 2,7% - excessive drinking. Only 8,7% women decreased alcohol consumption during pregnancy, while 20,7% increased the amount of alcohol consumed between 1st and 2nd or between 2nd and 3rd trimester. Gestational consumption of ethanol was not related to socio-demographic characteristics, course of pregnancy and self-reported health behaviors but babies of women who increased alcohol consumption during pregnancy were more often small for gestation age (weight <10 pct) than babies of women abstaining from alcohol throughout the pregnancy (p=0,003).

Conclusions. For the first time in Poland, this study objectively assessed alcohol consumption during pregnancy, confirming the usefulness of maternal hair analysis in detecting gestational ethanol use.  The results emphasize the need to implement preventive strategies regarding alcohol consumption during pregnancy.