OBJECTIVES: This study investigated the efficacy of screening for risk drinking during pregnancy with two brief questionnaires, TWEAK and T-ACE. Both include an assessment of tolerance based on the number of drinks women report they can hold. METHODS: Subjects were disadvantaged African-American obstetric patients in Detroit, Mich. Traditional alcoholism screens (Michigan Alcohol Screening Test [MAST], CAGE) and the tolerance question were administered (n = 2717); TWEAK and T-ACE were constructed from tolerance and embedded MAST and CAGE items. In a separate sample (n = 1420), only the T-ACE was administered. Periconceptional risk drinking was the gold standard. Screen evaluations were based on receiver-operating characteristic analyses. RESULTS: At the cutpoint of 2, sensitivity/specificity for embedded screens were 91/77 for TWEAK and 88/79 for T-ACE; comparable values for T-ACE alone were 67/86. TWEAK and T-ACE screened more effectively than CAGE or MAST. CONCLUSIONS: Embedded versions of TWEAK and T-ACE were both highly sensitive to periconceptional risk drinking in this population. Administering T-ACE alone reduced its sensitivity; this suggests that MAST and CAGE administration improves its performance.