There are two main reasons to consider for delayed menstruation despite ejaculation in vitro: 1. Patients fail in contraception by ejaculation in vitro and have an unplanned pregnancy that leads to the inability to have menstruation, because men may have prostatic fluid and sperm flowing in the female vagina before ejaculation in vitro, and if there are stronger sperm in the outflow, they may pass through the patient’s cervix and uterine cavity and enter the fallopian tube to rendezvous with the egg and form a fertilized egg and become pregnant, therefore Therefore, the patient must check the blood and urine HCG to determine whether she is pregnant or not; 2. Consider that the patient has delayed menstruation. If it is more than 1 week, ultrasound can be done to observe the thickness of the endometrium, and depending on the thickness of the endometrium, the decision can be made whether to wait for the menstruation or to use drugs to promote the menstruation.