The aim of this study was to determine the incidence and evolution of the atypical glandular cells of undetermined significance (AGUS) without associated lesions identified on cervical Pap smear. Retrospective study concerning 33.923 cervicovaginal smears performed in the Cytopathology Department of the Coimbra University Hospital (H.U.C.) between January 1995 an December 1997. AGUS diagnosis, isolated or associated with other lesions, was made in 716 cases. Four hundred fourty-four of them were refered to patiens of the H.U.C. Ginecology Department. One hundred seventy-seven cases were classified as AGUS alone; 62 related to the Ginecology Department where follow-up was performed within a period from 3 to 36 months. This study concerns exclusively AGUS patients without associated lesions (N=62). Sixty two cases of isolated AGUS were studied; the incidence was 0,52% and the average age 44,7 ±11,7 [19-75] years old. Follow-up, performed between 3 and 36 months, revealed: isolated cervical smears (N=9), cervical smears and endocervical curettage (N=15), cervical smears with colposcopy and directed biopsy and/or endocervical curettage (N=11), cervical smears and colposcopy (N=19). Total histerectomy was performed in 8 cases by other reasons. Cervical smears were normal in 91,2 % of the cases (N=62). Histologic examination of surgical samples refering to total histerectomy, cervix biopsies was normal in 14 cases (38,9%), revealed cronic cervicitis in 14 cases, LSIL in 7 cases and endocervical polyps in one case. In spite of the reduced data of the study, the results point to no need to an agressive therapeutical approach at AGUS diagnosis in Pap smears.