Mammary hypertrophy or macromastia can cause a wide range of symptoms (physical, psychosomatic or behavioral), which affect patients' quality of life. Breast reduction can, in most of the cases, solve the problem. However, certain factors could have a negative effect on the outcome of surgery. The aims of this study were to discover the degree of patient satisfaction (short- and long-term) and to evaluate results of reduction mammoplasty, and also to ascertain which factors may have a negative role on the effectiveness of breast reduction surgery. We carried out a prospective and longitudinal study of 121 patients who underwent breast reduction surgery. Quality of life, outcome of surgery (complications and sequelae) and degree of patient satisfaction were evaluated at 1month and at 1year after reduction mammoplasty. Mean patient age was 40.71 (SD=12.02). Among them, 35.5% were overweight, 44.6% were obese and 34.7% were smokers. The most common symptom was pain. The mean amount of resected breast tissue was 1785g (SD=876). A total of 27.3% of the patients suffered complications and 30.60% suffered sequelae. Our results show an improvement in symptoms (p<0.001) and quality of life (p<0.001 to p=0.002) 1month after and 1year after breast reduction compared with the preoperative situation. Neither age, body mass index, smoking habit nor the amount of tissue removed had a negative effect on the results of surgery. One year after surgery, the majority of patients were satisfied with the outcome (96.6%), they would recommend it to others (96.6%), and they would undergo surgery a second time (95.8%). Conclusions: Breast reduction is highly efficient in resolving symptoms and in improving quality of life. It leads to a high level of short- and long-term satisfaction irrespective of each patient's individual characteristics.