If you have nausea after 10 days of intercourse, it is possible that you are pregnant and it is advisable to go to the hospital to have a blood test for chorionic gonadotropin. Usually, about a week after intercourse, if conception is successful, the body will secrete a large amount of chorionic gonadotropin, which can be detected by a blood test to determine whether the pregnancy is present. The secretion of large amounts of human chorionic gonadotropin can cause gastrointestinal motility to slow down, resulting in stomach discomfort and pregnancy reactions such as nausea and vomiting. If two red bars appear on the early pregnancy test, you can be sure that you are pregnant. During early pregnancy, pay attention to rest, avoid overexertion, pay attention to folic acid supplementation and prohibit intercourse.