The prolongation of menstruation for more than ten days mostly refers to the delay of menstruation for more than ten days, which may be related to pregnancy, drug factors, endocrine disorders and so on. 1. pregnancy: for women who have sex, and do not take effective contraception during sex, menstruation is delayed for ten days, there is a possibility of pregnancy. 2. Drugs: some women regularly take contraceptive drugs, which may inhibit the secretion of endogenous hormones in the body and change the morphology of the endothelium, so the phenomenon of delayed menstruation will also occur. 3. Endocrine disorders: some women usually have too much mental stress, often stay up too late, emotional fluctuations, etc. may lead to hormone secretion disorders in the body, thus delaying menstruation. In addition to the above reasons for delayed menstruation, surgical factors, polycystic ovary syndrome, hyperprolactinemia, etc., may also lead to delayed menstruation. Under normal circumstances, menstruation about seven days in advance or delayed, is within the normal range, the phenomenon of delayed menstruation for more than ten days, it is recommended to go to the hospital in a timely manner, to clarify the cause of the disease, and then for the cause of the treatment.