evidence: - Cervical cancer is caused by persistent infection with the human papillomavirus (HPV). Women living with HIV are 6 times more likely to develop cervical cancer compared to women without HIV. [...] Persistent HPV infection of the cervix (the lower part of the uterus or womb, which opens into the vagina – also called the birth canal) if left untreated, causes 95% of cervical cancers. Typically, it takes 15–20 years for abnormal cells to become cancer, but in women with weakened immune systems, such as untreated HIV, this process can be faster and take 5–10 years. Risk factors for cancer progression include the grade of oncogenicity of the HPV type, immune status, the presence of other sexually transmitted infections, number of births, young age at first pregnancy, hormonal contraceptive use, and smoking. [...] As of 2023, there are 6 HPV vaccines available globally. All protect against the high-risk HPV types 16 and 18, which cause most cervical cancers and have been shown to be safe and effective in preventing HPV infection and cervical cancer.As a priority, HPV vaccines should be given to all girls aged 9–14 years, before they become sexually active. The vaccine may be given as 1 or 2 doses. People with reduced immune systems should ideally receive 2 or 3 doses. Some countries have also chosen to vaccinate boys to further reduce the prevalence of HPV in the community and to prevent cancers in men caused by HPV.