Cytohormonal evaluation was done on the vaginal smears of 480 normal, asymptomatic, post-menopausal women whose ages ranged from 36 to 74 years. About 50% showed atrophic smears consistent with total oestrogen lack. 41% had mild to moderately proliferative smears compatible with sub-optimal oestrogen stimulus. 9% showed a highly proliferative pattern typical of unopposed oestrogen effect and in this group two women had atypical endometrial cells in their smears, which subsequently were found to come from an atypical endometrial hyperplasia and an endometrial adenocarcinoma-in-situ. The clinical relevance of cytohormonal studies in post-menopausal women is briefly discussed.