The recommended age for cervical cancer quadrivalent and nine-valent vaccines in mainland China is between 20-45 years old for the quadrivalent vaccine and between 16-26 years old for the nine-valent vaccine. Of course, in Hong Kong, this age indication is different from that in mainland China, and the main consideration is the overall social benefits such as inputs and benefits. You can choose the vaccine that you can take in conjunction with the age group you are in. Both the quadrivalent vaccine and the nine-valent vaccine have definite effects on preventing HPV infection and cervical cancer. Because about 70% of cervical cancers are caused by HPV high-risk types 16 and 18 infections, both vaccines include components to prevent these two viruses, so either vaccine chosen will provide protection.