Most women with a 13mm thick lining will get their period within 1 week, but some women may get their period in about 2 weeks. However, if more than 2 weeks does not come to menstruation, it may be that the patient has irregular menstruation, pregnancy or gynecological diseases, and the time to come to menstruation is uncertain. 1. Irregular menstruation: Under normal circumstances, the thickness of the endometrium before the onset of menstruation is between 12-15mm. If the endometrium exceeds 15mm for more than 2 weeks and is still not shed, consider the possibility of menstrual irregularity due to progesterone deficiency. At this time, progesterone can be used to regulate the menstrual cycle under the guidance of a professional doctor, such as taking progesterone or progesterone injection; 2. Pregnancy: If more than 2 weeks without menstruation and you have had sex during ovulation, it may be caused by pregnancy; 3. Gynecological diseases: If the patient suffers from some gynecological diseases, such as common endometrial polyps and submucosal fibroids, it can make the patient have pseudo-endometrial thickening, and is not a true endometrial thickening and requires surgical treatment.