Detection of human papillomavirus DNA in biopsy-proven cervical squamous intraepithelial lesions in pregnant women.

This study analyzed cervical squamous intraepithelial lesions (SILs) in pregnant women for human papillomavirus (HPV) using in situ hybridization analysis. HPV DNA was detected in 77% (23/30) of low-grade SILs as compared to 89% of such lesions in nonpregnant women. The detection rate in high-grade SILs was 41% (9/22) compared to 70% in nonpregnant women. Analysis by the polymerase chain reaction showed that the detection rates were similar (96-100%) for low- and high-grade lesions in pregnant and nonpregnant women, which demonstrates that in situ negative tissues indeed contained HPV DNA. Low-grade SILs contained a heterogeneous group of at least 14 different HPV types, whereas most high-grade SILs contained HPV 16. We concluded that cervical SILs in pregnant women are invariably associated with HPV. Further study is needed to determine which of several possible variables, such as the age of the lesion and the viral copy number, may explain the apparent decreased detection rate of HPV by in situ hybridization in SILs during pregnancy.