Fluid dark zones found in pregnancy are usually referred to as uterine fluid, and fluid dark zones larger than 30mm are considered more serious.
Most of the fluid dark areas are caused by bleeding due to capillary rupture caused by stripping of the uterine wall from the gestational sac. They may also occur during shorter pregnancies.
There is no absolute conclusion as to how many millimeters of fluid dark zone is more serious. A fluid dark zone of 10-20mm may be related to physiologic fluid dark zone, inflammation, etc. If the patient is not accompanied by abdominal pain, lumbar pain, vaginal bleeding and other uncomfortable symptoms, it can be left untreated, and attention should be paid to rest and observation.
If the fluid dark area is very obvious, more than 30mm, it means that there is more fluid, bleeding is more serious, in this case the risk of miscarriage may be relatively high, which is considered a more serious fluid dark area.
It is recommended that the patient should consult a doctor for examination in time, and carry out fertility preservation treatment after clarifying the condition, so as to avoid spontaneous abortion, embryonic arrest, or other undesirable pregnancies.