14-year-old girls with delayed menstruation, the vast majority of reasons may have the following: First, in school to participate in exams, exam preparation, resulting in mental tension and endocrine disorders caused by delayed menstruation. In this case, it is recommended to take progesterone orally to promote menstruation, generally 3-7 days after stopping the drug will come to menstruation, it is recommended to take progesterone orally before going to bed to avoid the occurrence of dizziness. Second, as parents must ask whether the child has a history of sexual life, whether in love, if it is in love with a sexual life, may be caused by pregnancy, must go to the hospital for early examination, according to the results of the examination to determine the next step of how to treat. Third, it is recommended that 14-year-old girls drink less frozen drinks in their daily life, if they drink too many frozen drinks, it may lead to delayed menstruation. Fourth, pay attention to the regularity of life to avoid endocrine disorders that may lead to delayed menstruation.