As part of a mass cytologic screening program, cervical scrapings and endocervical/endometrial aspirations were taken from 1,250 women with systemic schistosomiasis. Ova of S. mansoni were found associated with two cases of carcinoma in situ and one case of invasive squamous cell carcinoma of the uterine cervix. In a fourth case, the ova were associated with a benign cervical lesion.