HCG is best measured about 10 days after intercourse. HCG refers to human chorionic gonadotropin, which begins to be secreted about 1 day after the fertilized egg has been deposited, and at this time, pregnancy can be confirmed by testing the HCG level in the mother’s peripheral blood. When the HCG blood concentration is >25 U/L, it is considered positive for pregnancy. Women with regular menstrual cycles can best confirm pregnancy by testing the blood HCG level about 10 days after intercourse. HCG in urine will appear later than blood HCG, so urine HCG test can usually be performed after the menstrual period is overdue, and it is recommended to use morning urine for more accurate testing. However, whether the pregnancy is confirmed by blood or urine HCG test, ultrasonography should be performed as prescribed by the doctor to clarify the intrauterine pregnancy, and also to rule out ectopic pregnancy, gravida and other pathological pregnancies.