Longitudinal Study of the Effects of Pregnancy and Other Factors on Detection of HPV

Abstract

Objective: An epidemiologic study of 108 pregnant and 192 nonpregnant women was carried out to determine the effects of pregnancy and other factors on the detection of HPV infection, since both or larger numbers of pregnancies and HPV infection are known to be risk factors for cervical cancer. Patients and methods: Study participants were followed up at 3-months intervals for a period of 15 months (1–6 months after delivery). At each visit, two cervical specimens were taken, one for routine cytology and a second for HPV DNA hybridization using Virapap/Viratype, and a 5-ml blood sample was taken and a self-administered questionnaire was completed. Results: In cervical specimens of the initial examination, HPV DNA was detected among 5.0% of pregnant and 5.2% of nonpregnant women, whereas HPV 16/18 was found in 80% of the HPV-positive specimens. Using multiple cervical specimens taken over time, 13.9% of the pregnant and 15.1% of the nonpregnant women tested positive for HPV DNA at least once. Adjusted for study group, age, and the number of available cervical specimens, ever detection of HPV infection (any type) was associated with more sexual partners and larger numbers of cigarettes smoked daily. An autoregressive generalized linear model was used to analyze the time-dependent multiple observations per study subject. Adjusting for age and trimester of pregnancy, the determinants of detecting high-risk HPV types (16/18 and 31/33/35) in the cervical specimen were an abnormal Pap smear, a positive HPV result in a preceding specimen, more than six sexual partners in the lifetime, and currently smoking more than 20 cigarettes per day with odds ratios of 10.9, 5.6, 3.2, and 2.7, respectively. Conclusion: Our data provide no evidence for a higher detection rate of HPV during pregnancy.