Symptoms of vaginal bleeding on the 40th day of pregnancy without abdominal pain may be bleeding caused by preeclampsia. After pregnancy, a variety of conditions may cause preeclampsia, such as stress, exhaustion, weight-bearing, excessive stress, insufficient progesterone, mycoplasma infection, chlamydia infection, TORCH infection, and poorly developed embryo, all of which may cause vaginal bleeding. Abdominal pain does not necessarily occur when there is vaginal bleeding; it occurs when there are contractions. Even if there is no abdominal pain after pregnancy, vaginal bleeding should be taken seriously, and an abdominal ultrasound, as well as blood HCG, progesterone and other related tests are needed to check the development of the embryo, whether it is an intrauterine pregnancy and whether there is a progesterone deficiency. If the development of the embryo is normal, under the guidance of the doctor, carry out fertility preservation treatment, pay attention to bed rest, and observe whether the symptoms improve.