Information on socioeconomic background, maternal diseases and obstetric history, parity, gender, fetal exposure to alcohol (at least 2 drinks a week during the
entire pregnancy) and cigarette smoking (at least 1 cigarette a day during the last trimester), type and
duration of breastfeeding, and maternal intelligence (Raven Progressive Matrices) was obtained through questionnaires administered in person after delivery and at 13 months.