If the patient does not have brown vaginal discharge before intercourse in the early stage of pregnancy, but brown discharge appears after intercourse, there are two main possibilities: first, the intercourse is too strong, stimulating the patient’s uterus and cervix, resulting in vaginal bleeding and other cases of pre-eclampsia, in this case, gynecological ultrasound, blood progesterone and HCG check, observe the situation of the embryo, if necessary, the use of drugs to protect the fetus. Secondly, the patient may have cervical or vaginal lesions that cause contact bleeding during intercourse, such as inflammatory diseases, polyps or tumor diseases, etc. In this case, gynecological internal examination is needed, and if necessary, cancer-related screening is required. Therefore, in the early stages of pregnancy, especially in the first 3 months of pregnancy, try not to have intercourse.