The quadrivalent vaccine is a vaccine that prevents cervical cancer. It is a viral vaccine that prevents HPV infection but does not usually cause menstrual irregularities. There are many reasons why women experience irregular periods, such as changes in lifestyle habits. Some women stay up too late and work too hard, are overly stressed, or are struck by some special event in their lives, all of which can cause irregular periods. In addition, excessive weight loss, not eating, etc. can also cause menstrual changes. In addition, changes in hormone levels, such as increasing age or poor rest, can affect the abnormal secretion of hormones. So if you have abnormal menstruation, you should visit the hospital first to find out the cause and vaccines are not related.