Objective. Describe physicians' practices of smoking cessation and secondhand smoke (SHS) exposure counseling during prenatal visits. Design. Cross-sectional survey. Setting. A total of 13 public and private hospitals from three cities in Argentina. Population. A total of 300 obstetrician/gynecologists. Methods. Self-administered survey included knowledge and attitudes about tobacco use during pregnancy, frequency, type and duration of smoking cessation counseling, barriers to counseling, communication skills, level of understanding and personal smoking history. Main outcome measures. Composite outcomes of four items, each representative of counseling on smoking cessation and SHS exposure. Results. A total of 235 (78.3%) questionnaires were completed; 54.5% men, mean age 45, 35% current smokers. Only 22% had received training in smoking cessation counseling and 48.5% reported insufficient knowledge to provide smoking cessation advice. Although 88.9% always or almost always advised women to stop smoking, 75% believed it was acceptable for pregnant women to smoke up to 6 cigarettes per day. The risk of SHS exposure was ‘always or almost always discussed’ by only 34.5% of physicians. Multivariate logistic regression showed that lack of training was associated with less counseling about smoking cessation (OR 0.18; 95% CI 0.04–0.82) and SHS exposure (OR 0.27; 95% CI 0.12–0.59). Current compared to never smokers had lower odds of smoking cessation counseling (OR 0.39; 95% CI 0.05–0.82). Current smokers were less likely than former smokers to counsel about SHS (OR 0.25; 95% CI 0.11–0.62). Conclusions. Smoking cessation counseling during pregnancy in Argentina occurs infrequently, interventions are needed to assist physicians motivate and counsel women to quit smoking and avoid SHS exposure. Physicians taking care of pregnant women also need to quit smoking.