Serum concentrations of oestrone, oestradiol and oestriol were measured in 23 postmenopausal women, 12 with ovarian cancer and 11 with genital prolapse. Oestrone (387.6 pmol/l) and oestradiol(72.7 pmol/l) levels were higher in the cancer group than those in the control group (159-8 and 27.5 pmolil respectively), while oestriol levels did not differ (434.5-270-8 pmolil). T h e results indicate abnormal ovarian function in postmenopausal patients with ovarian cancer.