We aimed to identify drinking rates in a prospectively identified cohort of pregnant women, and subsequently, to identify the drinkers of 48 g or more alcohol/day among them, by using complementary methods for verifying self-reported drinking habits. A research team of social workers and health professionals at the Maipú Clinic, located in a lower middle class neighborhood of Santiago, Chile, conducted interviews of women attending a prenatal clinic between August 1995 and July 2000. Women whose interview responses met predefined criteria (identified in the text) were further evaluated by home visits. We interviewed 9,628 of 10,917 (88%) women receiving prenatal care. By initial interview, 42.6% of women reported no drinking, 57.4% some alcohol consumption, and 3.7% consuming at least one standard drink (15 mL of absolute alcohol) per day. Of the 887 women who had home visits, 101 were identified as consuming on average at least 4 drinks/day (48 g). To determine the best home visit questionnaire items for identifying those drinking at least 4 drinks per day, 48 women who openly admitted drinking this amount were compared with 786 women who were not considered drinkers after the home visit. The 48 self-reported 48 g/day drinkers were significantly more likely to get tipsy when drinking before (p = 0.01) or during (p