Pregnancy-associated thrombocytopenia: Pregnancy-associated thrombocytopenia is caused by the increase in blood volume after pregnancy and the decrease in relative platelets rather than the increase in platelet destruction, the degree of platelet decline is small, the disease is relatively mild, and it can recover on its own after delivery; 2, pregnancy-associated idiopathic thrombocytopenic purpura. The platelet drop is more serious, the hemoglobin and leukocytes are normal, the megakaryocytes are significantly increased with maturation disorder, if not actively treated, more harmful; 3, HELLP syndrome: that is, hemolysis, elevated liver enzymes, thrombocytopenia syndrome, refers to a group of clinical syndromes of hemolysis, elevated liver enzymes and thrombocytopenia on the basis of hypertensive disease in pregnancy, because the syndrome is a serious complication of pregnancy. HELLP syndrome progressive, only termination of pregnancy can effectively eliminate the cause and improve the prognosis of mother and child, once diagnosed within 48 h termination of pregnancy, especially when fetal distress, deterioration, suspected DIC, should end delivery as soon as possible, delayed delivery can cause adverse consequences; 4, other relatively rare diseases: diffuse intravascular hemolysis, drug-induced thrombocytopenia, rheumatic Immune diseases, acute leukemia, megaloblastic anemia, etc. Thrombocytopenia during pregnancy is a common bleeding disorder, which is harmful to mother and child and is prone to recurrence, especially during delivery, surgery and anesthesia, which can cause serious bleeding and affect the outcome of pregnancy.