If you have a normal menstrual cycle, you can usually test for pregnancy 15 days after intercourse.
If a woman has a normal menstrual cycle of about 28-30 days, then the ovulation date is about 14 days before the next menstrual period. If you have intercourse during ovulation, the chances of getting pregnant are very high. When a woman gets pregnant, the embryo will usually settle in the lining of the uterus about a week after intercourse.
After the embryo is implanted, the woman’s body will secrete human chorionic gonadotropin (HCG), which can be detected in the blood to determine whether or not she is pregnant.
However, because the urine test for human chorionic gonadotropin is not as sensitive as the blood test for human chorionic gonadotropin, if you want to determine whether you are pregnant through the urine test, the earliest you can detect it is 15 days after intercourse.
Women who usually have normal menstrual cycles, usually 15 days after intercourse, if the pregnancy can be detected through the test paper, it is recommended that women who have delayed menstruation, to seek medical attention as soon as possible.