Early pregnancy uterine fluid is usually a blood accumulation in the uterine cavity, which may be caused by preeclampsia, bleeding from the gestational sac, ectopic pregnancy, etc. It is recommended to further improve the relevant examinations to identify the cause. 1. Pre-eclampsia: Early pregnancy with uterine fluid, usually refers to abnormal bleeding in the uterine cavity, belongs to the manifestation of pre-eclampsia, may be insufficient luteal function, resulting in the decline of progesterone caused by the embryo itself may be the quality of the embryo itself is not good and the abnormal bleeding. You need to take proper rest, avoid strenuous exercise, and take progesterone and other medications to preserve the fetus if necessary. 2. Bleeding from the gestational sac: the local endometrial blood vessels can be stimulated during the gestational sac’s implantation and cause bleeding. If the bleeding is large and not absorbed in time, it can accumulate around the gestational sac and cause uterine effusion. 3. Ectopic pregnancy: due to the fertilized egg in the uterine body cavity outside the bed, the female body estrogen progesterone level can directly stimulate the endometrium proliferation, resulting in the accumulation of blood in the uterine cavity, usually accompanied by pain in the lower abdomen, urinary frequency, vaginal discharge increase and other symptoms. Early pregnancy ultrasound found in the uterine cavity fluid, should pay attention to, timely consultation, identify the cause of the disease, so as to avoid abnormalities, affecting the growth of the fetus.