If menstruation is delayed after the first period, it may be due to ovarian gonadal function not yet developed or endocrine disorders caused by mental tension, overwork, lack of sleep, or dieting. Usually, it is normal to delay menstruation for not more than 7 days and there is no need to worry about it, but if it is more than 7 days, you should go to the hospital in time to rule out any other organic diseases. If a woman has a delayed period after her first sexual intercourse, it is usually related to pregnancy, endocrine disorders or some chronic diseases.1. Pregnancy: If no protective measures are taken during sexual intercourse and the woman is in ovulation, it may lead to pregnancy and thus a delayed period. The diagnosis can be confirmed by early pregnancy test paper or blood HCG test at the hospital. 2. Endocrine disorder: Seasonal change, sudden climate change, environmental pollution, insomnia, long night stay, depression, anxiety, etc. can lead to endocrine disorder, which can lead to menstrual disorder. The endometrial condition can be observed by ultrasound examination, and if necessary, drugs can be used under the guidance of doctors to promote menstruation, such as progesterone, motherwort granules, etc.; 3. Chronic diseases: such as hypothyroidism, severe anemia, etc., often lead to delayed menstruation. For the delayed menstruation caused by chronic diseases, you should go to the hospital to identify the cause and treat the cause in a timely manner. For example, hypothyroidism needs to take levothyroxine sodium tablets as prescribed by the doctor, and severe anemia can be treated with oral ferrous succinate tablets as prescribed by the doctor.