morbid obesity in women is associated to a lower prevalence of thyroid nodules background few studies have recently showed functional and morphological changes of the thyroid gland in relation to obesity to our knowledge no data are available about the prevalence of thyroid nodules in female obese patients the aim of this study was to investigate the prevalence of thyroid nodules in morbidly obese womenmethods one hundred eight consecutive female obese patients were selected from those referred to our medical and surgery outpatients providing that following criteria were satisfied 1 affected by morbid obesity body mass index bmi 40 kgm2 2 no previous diagnosis of thyroid disease 3 biochemically proven euthyroid state at the time of recruitment ninetyseven control subjects constituted by normoweight andor slightly overweight bmi30 kgm2 women should satisfy the above criteria 2 and 3 all the subjects were submitted to ultrasound investigationresults the two groups of patients displayed no differences for age and ft4 levels obese patients clearly showed a lower prevalence of thyroid nodules odds ratio 0294 95 confidence interval 02060382 a single nodule was found in 23 of obese patients as compared to 65 of control subjects p00001 no difference for age year was found between obese and nonobese subjects with nodules 40582 vs 44289 respectively p007conclusions our data clearly show a significantly lower prevalence of thyroid nodules in morbidly obese patients further studies are needed to confirm and to understand this first observation