Pregnancy is a major event in every woman’s life, and how to have a healthy baby is a topic of concern for every mother-to-be. In addition to hematocrit and white blood cells, platelets are of particular concern to doctors. This is because platelets are closely related to the coagulation system, and the presence of reduced platelets during pregnancy may indicate a disease. The most common one is idiopathic thrombocytopenic purpura (ITP), mainly due to autoantibodies binding to platelets, causing shortened platelet survival, which can be diagnosed by bone aspiration and platelet antibodies. The diagnosis of ITP during pregnancy does not require interruption of pregnancy, but the disease is potentially dangerous to pregnancy, the mother may have bleeding tendency, vaginal bleeding after delivery, intracranial hemorrhage may occur if the mother holds her breath during delivery The disease can cause bleeding tendency, vaginal bleeding after delivery, intracranial hemorrhage during labor and breath-holding, postpartum hematoma and postpartum hemorrhage in the birth canal and abdominal surgical incision, and even life-threatening internal bleeding in severe cases. If a pregnant woman has only thrombocytopenia and no significant bleeding tendency, she can be given general treatment, such as vitamin C, lutin, etc., and regular rechecking of platelets and strengthening monitoring of the fetus. If bleeding is severe, adrenocorticotropic hormone therapy can be used, and if necessary, single platelet transfusion. Thrombocytopenia can also be seen in immune system disorders, commonly systemic lupus erythematosus (SLE), and is often accompanied by leukopenia and anemia. The disease has a high prevalence in women of childbearing age, with clinical manifestations such as pteroidal erythema (seen in 80% of SLE), arthralgia and muscle pain, as well as systemic manifestations such as fever and malaise, which can be confirmed by anti-nuclear antibody profile and skin lupus band test. In the past, pregnancy and childbirth were once contraindicated in SLE, but nowadays most SLE patients can safely have a pregnancy after disease control, but cytotoxic immunosuppressants need to be stopped for more than six months before pregnancy, otherwise it will affect fetal growth and development. Of course, thrombocytopenia can also be seen in megaloblastic anemia, DIC, myelodysplastic syndrome and hypersplenism of liver cirrhosis, but it is rare in women of childbearing age, so we will not go into details here.