Effect of second pregnancy on maternal carriage and outcome of high-risk human papillomavirus (HPV). Experience from the prospective finnish family HPV study.

OBJECTIVES: The effect of second pregnancy on human papillomavirus (HPV) carriage and outcome is modelled in longitudinal setting covering two subsequent pregnancies. STUDY DESIGN: Among 329 (baseline pregnant) women prospectively followed up in the Finnish Family HPV Study, two subcohorts were compiled: (i) 78 women (Group B) who became pregnant for the second time during the follow-up, and (ii) 100 women (Group A) who did not develop 2nd pregnancy. The effect of pregnancy on high-risk HPV (HR-HPV) carriage and outcome was analysed using Kaplan-Meier and Cox survival analyses and generalized estimating equation (GEE) modelling of the longitudinal data. RESULTS: Women in the two groups were similar in their baseline HR-HPV status but significantly different in several known risk factors of HR-HPV infection. Group A women showed higher point prevalence of cervical and oral HR-HPV at the 36-month (p = 0.015) and 6-month (p = 0.024) follow-up visit, respectively. Among Group B women, prevalence of both cervical and oral HR-HPV significantly decreased during 2nd pregnancy (p = 0.005 and p = 0.002) as compared with inter-pregnancy period, but increased again after 2nd pregnancy. There was no difference in acquisition or clearance of cervical or oral HR-HPV between the two groups in univariate (Kaplan-Meier) or multivariate (Cox) survival analysis. In the GEE approach, 2nd pregnancy was not significantly associated with cervical or oral HR-HPV carriage or persistence when adjusted for all other covariates. CONCLUSIONS: Second pregnancy is of little impact on carriage and persistence of oral and cervical HR-HPV infections in a longitudinal setting over time.

Human papillomavirus in the placenta and umbilical cord blood.

OBJECTIVE: To analyze human papillomavirus (HPV) DNA in umbilical cord blood and in placenta, including its cellular localization. DESIGN: Longitudinal prospective study. SETTING: Maternity Unit of Turku University Hospital, and MediCity, University of Turku. SAMPLES: Placental and cord blood samples obtained at delivery from 315 mothers and 311 neonates included in the Finnish HPV Family Study. METHODS: HPV testing by nested PCR and sequencing. Tyramide amplified in situ hybridization (ISH) for viral DNA localization in placenta. Correlation to mother's and neonate's oral and genital HPV status and maternal demographic data. MAIN OUTCOME MEASURES: Detection and cellular localization of HPV DNA. RESULTS: HPV DNA was detected in 4.2 and 3.5% of placenta and cord blood samples, respectively, including HPV types 16, 6, 83 and 39. In placenta, HPV6 and 16 DNA was localized in syncytiotrophoblasts. Abnormal cytology increased the risk of HPV+ placenta and cord blood. History of genital warts was the only independent predictor of cord blood HPV in multivariate analysis (adjusted OR=4.0, 95% CI: 1.09-14.54, p=0.036). HPV DNA in cord blood increased the risk of genital (OR=4.0, 95% CI: 1.08-14.83, p=0.048) and oral (OR=4.4, 95% CI: 1.17-16.14, p=0.039) HPV DNA carriage of the neonate. HPV+ placenta increased the risk of oral HPV of the neonate (OR=8.6, 95% CI: 2.73-27.13, p=0.0001). Delivery mode did not predict HPV status of the neonate. CONCLUSIONS: HPV DNA is detected in placental trophoblasts and umbilical cord blood. The presence of HPV DNA at these sites increases the risk of a neonate testing HPV-positive at birth.