A sample of women attending a gynaecological outpatient clinic were examined for symptoms and objective signs of fluid retention. Patients completed a questionnaire on symptoms suggesting fluid retention and recorded daily weight and abdominal girth variation. Daily weight variation varied from 0-9 pounds (mode 2 pounds) with no discernable difference between premenstrual and intermenstrual variation. Daily girth variation varied from 0-6 inches (mode 1 inch). Symptoms of breast swelling were more common premenstrually, finger/hand and ankle swelling intermenstrually and abdominal swelling occurred with equal frequency in both periods. No correlation between symptoms and weight variation was seen although abdominal swelling and girth variation were associated (P less than 0.04). The results indicate that symptoms of mild fluid retention and of diurnal weight and abdominal girth variation are part of the everyday experience of our study population. There is no clear-cut separation between 'normal' and 'abnormal' fluid retention (idiopathic oedema, periodic oedema, fluid retention syndrome); the latter may be an exaggeration of normal fluid-retaining mechanisms common to most women or may represent a pathological state. An approach which evaluates individual risk factors and the severity of fluid retention in each patient is recommended.