It is possible to get pregnant even if your period is delayed for 5 days. Pregnancy is possible as long as there is no contraception during ovulation, even if your period is delayed for 3 days. In this case, it is recommended to perform a blood HCG test. If the HCG value is high, it indicates pregnancy, which is usually the case. Ultrasound may not detect an intrauterine or ectopic pregnancy around 5 days of pregnancy, so you can wait for about 7-10 days for an ultrasound to find out the size of the gestational sac and the location of the implantation. If the child is retained, eugenics tests can be performed, such as the four eugenics tests, blood type, routine blood tests, and folic acid bioavailability tests, etc. Depending on the results of the folic acid bioavailability tests, oral folic acid can be taken to prevent the occurrence of fetal neurospinal malformations.