Evaluation of serum gamma-glutamyl transferase as a screening method for excessive alcohol consumption during pregnancy.

Serum gamma-glutamyl transferase was analyzed in 669 pregnant women. They were interviewed with special emphasis on their consumption of alcohol during the first trimester. Thirteen percent admitted a consumption of greater than 30 gm of pure alcohol per day, and 3%, greater than 125 gm per day. One child with a complete fetal alcohol syndrome and one with a partial one were born to mothers with a high consumption of alcohol and elevated serum gamma-glutamyl transferase. The ninety-fifth percentile for serum gamma-glutamyl transferase in women classified as low consumers (less than 30 gm of alcohol per day) was 0.44 mukat/L. With this 95% specificity level used as a cutoff, the sensitivity of the serum gamma-glutamyl transferase test in identifying those who consumed more than 30 gm of alcohol per day was 25%. The conclusion was that screening based on analyses of serum gamma-glutamyl transferase is not to be recommended for routine use in prenatal care.