evidence: Cons - The HPV vaccine can cause side effects. However, these are rare. To date, no serious side effects have been shown to be caused by the vaccines. [...] Most people receive the HPV vaccine without having any serious side effects. Mild to moderate side effects occur more often but are still uncommon. Mild to moderate side effects can include: [...] Some people are concerned that HPV vaccination may have serious side effects or long-term impact, such as on fertility.