Influence of sexual activity on development of cervical intraepithelial neoplasia (CIN).

From July, 1977, through December, 1982, 342 patients were evaluated histologically. Aimed biopsy was performed on all cases because of the presence of colposcopic abnormality. Mild dysplasia was regarded as cervical intraepithelial neoplasia grade I (CIN1), moderate dysplasia as CIN2, and severe dysplasia with carcinoma in situ as CIN3. There were 81 CIN1 (24.0%), 32 CIN2 (9.5%), and 33 CIN3 (9.8%) cases. There was no significant influence of the age at first sexual contact, the age at first pregnancy, multiple partnership, sexual frequency, or the age of the patient on the development of CIN. Regular examination should be performed to detect CIN regardless of age, age at first sexual contact, and age at first pregnancy.