Brown discharge turning into pink color in early pregnancy is a sign of vaginal bleeding, which may be caused by pre-eclampsia, ectopic pregnancy, choriocarcinoma and other reasons. 1. Pre-eclampsia: Research shows that the common cause is chromosomal abnormality of embryo, followed by factors related to uterine dysplasia, endocrine function abnormality, severe physical stimulation, smoking, alcoholism, exposure to radioactivity, etc. Typical symptom is vaginal bleeding, but due to the amount is relatively small, so there will be the situation that brown discharge in early pregnancy turns into pink color. 2. Ectopic pregnancy: the causes of this disease include tubal inflammation, tubal dysplasia, pelvic inflammatory disease, contraceptive failure, etc. Patients will have symptoms such as menopause, abdominal pain, vaginal bleeding, and so on, so there will be a manifestation of brown secretion turning into pink color in early pregnancy. 3. Choriocarcinoma: the etiology of this disease is still unclear, research shows that it often occurs after gravida, miscarriage, ectopic pregnancy, and the main clinical manifestations are abdominal pain, pseudo-pregnancy symptoms, abnormal vaginal bleeding and so on. It is recommended that women whose brown discharge turns pink in early pregnancy should go to the hospital for timely consultation and examination, and follow the doctor’s instructions for treatment after clarifying the specific causes.