Mothers of the offspring included in the present report were administered a structured interview concerning their drinking, smoking, and drug usage during pregnancy. The interview was performed on the occasion of the first follow-up visit to the laboratory when children were on average 12.1 ± 3.3 years of age. The interview was designed in our laboratory with the goal of measuring quantity and frequency of drugs, alcohol, and cigarettes during each trimester of pregnancy. Mothers with multiple children were queried concerning each child separately. Three prenatal measures were derived from the interview of the mother: prenatal alcohol exposure (quantified as number of drinks during pregnancy), prenatal cigarettes exposure (number of cigarettes smoked during pregnancy), and number of drug days (representing number of days during pregnancy that the mother reported using drugs).
