There are two possibilities for women with a 10-day delay in menstruation: pregnancy or menstrual irregularities. If you have had sex before and have not taken any contraceptive measures, you can first consider the possibility of pregnancy, because if your period has been delayed for 10 days, you can test the middle part of your morning urine directly with a morning pregnancy test to see if you are pregnant. If it is convenient to go to the hospital, you can also go directly to the hospital to determine if you are pregnant by using human chorionic gonadotropin in the blood. If there is no sexual intercourse or if it is determined that there is no pregnancy, the irregular menstruation is usually caused by endocrine abnormalities, and the endometrial thickness and hormone levels need to be checked by ultrasound and treated accordingly.