Prevalence of human papillomavirus types 11, 16 and 18 in cervical swabs. A study of 1362 pregnant women.

Cervical smears from 1362 pregnant women were examined by filter in situ hybridisation for human papillomavirus (HPV) types 11, 16 and 18. 119 women (8.7%) had HPV-positive smears, HPV 16 being the most common type (61% of all infections). There was a correlation with age (r = 0.63, p = 0.004), the highest incidence found in women less than 22 years old with a decline after the age of 30. The incidence of cervical HPV infection was significantly higher (20.3%, p less than 0.01) in the subgroup of women with past or present vulvar condyloma, but not in women with previous pelvic inflammatory disease or genital herpes. In 18 women with current dysplasia the smears harboured HPV 16, 18, or both in eight cases (40%). The incidence of HPV infection in 71 women with earlier dysplasia did not differ from that of the women who never had dysplasia