The bivalent HPV vaccine requires three injections. Currently, we have the bivalent vaccine, the quadrivalent vaccine and the nine-valent vaccine, all three of which require three injections in our country. The bivalent vaccine is for women between the ages of 9 and 45 years old and protects against HPV types 16 and 18. After the first injection, a second dose is required after one month, and a third dose is required at the sixth month. There are also the quadrivalent and nine-valent vaccines, which require a second injection two months after the first injection, and a third injection at the sixth month. So when the three injections are finished, the body will produce antibodies, which will have a preventive effect on the HPV virus.