The appearance of black blood clots in the second month of pregnancy is considered to be a sign of preterm miscarriage, but it may also be a sign of embryonic dysplasia or cessation of development, normally vaginal bleeding will not occur during pregnancy, the appearance of vaginal bleeding is a signal to remind the presence of abnormalities, the most common cause is preterm miscarriage or embryonic dysplasia or cessation of development, gravida, ectopic pregnancy can also cause bleeding during pregnancy, but ectopic pregnancy in bleeding However, ectopic pregnancy will have different degrees of abdominal pain at the same time, so you need to go to the hospital in time to get a clear diagnosis through the results of HCG, progesterone and ultrasound examination. If the fetus is currently developing normally, it means that it is a pre-eclampsia miscarriage, which may be related to fatigue, sexual life or strenuous exercise, or there may be no clear cause, so you need to keep the fetus in time, pay attention to rest, avoid sexual life and strenuous exercise, and use medication as prescribed by the doctor.