The HPV vaccine cannot be given on the first day of menstruation mainly because the HPV vaccine itself has certain toxicity. Although menstruation is a normal physiological period for women, the hormone level in the body changes during the physiological period, so it will lead to corresponding changes in the body, resulting in a decrease in body resistance, etc. In the case of a decrease in body resistance, and the HPV vaccine with toxicity will have a greater impact on the body. Therefore, it is not recommended to take the HPV vaccine when you are having your period. In addition, HPV vaccine can not be given during breastfeeding, during pregnancy, if there is a serious medical disease, also can not be vaccinated and if there is a cold, fever, also can not be vaccinated, it is best to consult a doctor before vaccination, and then decide the time of vaccination.