In an attempt to detect the presence, if any, of cervical chlamydial infection, we obtained endocervical smears from 1000 female patients attending the outpatient gynecologic and family planning clinics at Women's Hospital, Zheijiang Medical University, Hangzhou, People's Republic of China. Using direct immunofluorescent monoclonal antibody staining technique, we identified elementary bodies typical of the Chlamydia trachomatis organism in ten of the 1000 slides (1%). The only characteristic of statistical significance in this small group of infected women was the complaint of infertility for more than two years' duration, noted in six of the ten cases.