About 10 days after having unprotected sex, a blood test can be done to detect HCG in the blood to confirm pregnancy. When a fertilized egg is deposited in the uterine cavity to form an embryo, the embryo will secrete a large amount of human chorionic gonadotropin (HCG) during its growth and development, and this hormone can circulate in the pregnant woman’s blood, so pregnancy can be confirmed earlier by drawing blood to test for HCG than by testing for it in the urine. If an ultrasound is performed, the presence or absence of a gestational sac in the uterus can be observed, mostly around 40 days after menopause, to determine an intrauterine pregnancy, and to rule out ectopic pregnancy, trophoblastic disease, and pelvic masses. In addition, early pregnancy test can also be used, a positive result indicates pregnancy, while a negative result indicates non-pregnancy, but the accuracy of the test is lower than that of the blood HCG test, and it can be detected at a later stage. After pregnancy, the body may also show relevant symptoms, such as menopause, early pregnancy reaction, etc. Women may have nausea, vomiting, drowsiness, sleepiness, and like to eat acidic or spicy food, and may also have frequent urination, breast enlargement, etc. Therefore, women can clearly identify whether they are pregnant or not through the relevant clinical manifestations, combined with the blood HCG test and ultrasound examination.