Background: Then is some evidence that hormone replacement therapy may produce significant improvements in fine wrinkling, while aging skin is more frequently found in smokers. However, studies of the combined effect of a protective factor, such as HRT, and a damaging factor, such as smoking, are rare. Objectives: To determine in postmenopausal women the relationship between smoking status and the average number of packets of cigarettes since the subject took up smoking (packs-years) on the one hand, and facial wrinkling on the other, and to evaluate the role of hormone replacement therapy in the prevention of wrinkles in smokers and non-smokers. Methods: All subjects were recruited from our menopause clinic at Hospital Clinic i Provincial in Barcelona and were placed into one of three groups according to their smoking status: 215 life-long non-smokers, 306 former smokers and 209 current smokers. Smoking status, pack-years and hormone replacement were assessed by direct questioning. Facial wrinkle scores were estimated by standardized visual assessment. Results: The relative risk of moderate-severe wrinkling for current smokers compared to that for life-long non-smokers was 2.57 (confidence interval: 1.83-3.06; P < 0.0005). Pack-years was positively related to facial wrinkles. Life-long non-smokers receiving HRT had lower facial wrinkle scores than Life-long non-smokers who had never received HRT. HRT did not, in general, modify the facial wrinkle score in current smokers. Conclusion: Our results suggest that the risk of facial wrinkles is greater in smokers and that HRT does not diminish this risk. (C) 1998 Elsevier Science Ireland Ltd.