If there is a liquid dark area in pregnancy, you need to pay attention to the size of the amount of the dark area when you have an ultrasound. If there is pelvic inflammatory disease, there will be liquid dark area in the uterine cavity, which will be accompanied by slight stomach pain. If it is not particularly serious, pay attention to rest, usually can be slowly improved. If it is more serious, you can take some anti-inflammatory drugs, amoxicillin or cephalosporin. If there is a pregnancy sac and uterine wall peeling, there will be a blood accumulation in the uterine cavity, which belongs to the first sign of miscarriage, this time will easily lead to a liquid dark area. If the amount of fluid dark area is not large, pay attention to bed rest, do not overwork. Don’t lift heavy objects during this period, and usually it can slowly return to normal. If the feeling is more serious, you can intramuscular injection of progesterone for fetal preservation treatment.