If you have been bleeding from the vagina for a month, you should consider the following 3 factors: 1) Pregnancy-related causes should be ruled out, such as monitoring of blood or urine HCG to rule out pregnancy and the possibility of pre-eclampsia or ectopic pregnancy; 2) Endocrine related, such as endocrine disorders. In addition to the influence of hypothalamic-pituitary-ovarian axis, menstruation also has a lot to do with external factors, such as weather change, geographical change, and dramatic weight gain or loss, which may affect a normal menstruation. 3. Cervical lesions should be excluded, and regular cervical cancer screening is recommended after having sex, so that early detection of cervical lesions and early treatment can largely reduce the incidence and mortality of cervical cancer. mortality.