Can HPV vaccine have other health benefits more than cancer prevention? A systematic review of association between cervical HPV infection and preterm birth.

Although the association between high-risk human papillomavirus (HPV) infection and cervical dysplasia as well as cervical cancer is well established, studies on the relationship between HPV infection and risk of preterm birth (PTB) have yielded inconclusive and inconsistent results. Therefore, we conducted a meta-analysis to investigate the association between HPV infection and PTB. The electronic database was searched until July 1, 2014. Relevant studies reporting the association between HPV infection and the risk of PTB were included and for further evaluation. Statistical analysis was performed using Revmen 5.3 and Stata 10.0. Six observational cohort studies and 2 case-control studies were included. A significant association between HPV infection and PTB was observed (odds ratio=2.12, 95% CI 1.51-2.98, P<0.001, random effect model). Stratification according to diagnostic methods indicated that both positive HPV DNA status and abnormal cervical cytology were associated with increased risk of PTB. Moreover, our data suggested a higher risk of PTB in Caucasian HPV-infected population, while no significant association was observed in the Asian population. Although the causality remains unclear, findings from our meta-analysis indicate that HPV infection might increase the risk of PTB. In the future, prospective cohorts with larger samples sizes are warranted to ascertain the causality and pathophysiological studies are required to explore the possible biological mechanisms involved.