Having menstruation twice a month is not necessarily a precursor of cervical cancer, but it can not be ruled out. There are also some diseases that can lead to menstrual disorders, such as anovulatory abnormal uterine bleeding, ovulatory abnormal uterine bleeding and so on. 1. Cervical cancer: long-term human papillomavirus infection can cause cervical cancer, especially invasive squamous cell carcinoma of ectopic type, which will show papillary or cauliflower-like tissues and bleed easily when touched, leading to irregular vaginal bleeding. If the lesion seriously invades the blood vessels in the mesenchymal stroma or the large blood vessels, it will cause a lot of bleeding, which can be mistaken as menstruation by some patients. This condition is usually accompanied by foul smell of secretion, like fishy smell or purulent malodor. 2. Not cervical cancer: (1) Anovulatory abnormal uterine bleeding: immature development of hypothalamus-pituitary-ovarian axis in puberty will result in anovulatory irregular menstrual cycles with bleeding intervals of different lengths. In addition, if the endometrium has a defective self-limiting mechanism, such as incomplete shedding of the endometrium and abnormal structure and function of the uterine blood vessels, all these factors will cause abnormal uterine bleeding. (2) Ovulatory abnormal uterine bleeding: luteal insufficiency affects progesterone secretion or premature luteal regression resulting in a shortened menstrual cycle, endometritis, chronic pelvic inflammation, or endometrial angiogenesis abnormality affects the endometrial local coagulation and fibrinolysis regulation mechanism, resulting in intermenstrual bleeding. If you have two periods in a month, you should consult a doctor for a comprehensive diagnosis and symptomatic treatment based on clinical symptoms and examination.