The prevalence of rheumatoid arthritis is 0.8 %, and its onset is most common between the ages of 35 and 50, being three times more common in women than in men. It is characterized by synovitis that primarily involves the peripheral joints, but can also lead to destruction of cartilage, bone erosion, and deformity of the joints. The rheumatoid factor can be positive and the titer of the rheumatoid factor correlates with the condition. In addition, 20% of patients can show positive antinuclear antibodies. I. Clinical manifestations The main manifestation is the involvement of joints, such as chronic polyarthritis, mainly distal small joints, mainly finger joints, wrist joints and knee joints. In addition, many patients may have extra-articular manifestations, such as rheumatoid nodules, vasculitis, pleuropulmonary symptoms, etc., but rheumatoid arthritis rarely involves the kidneys. Second, the relationship between pregnancy and rheumatoid arthritis Most patients’ condition is reduced during pregnancy, but the condition often worsens after delivery, and breastfeeding may also aggravate the condition. Rheumatoid arthritis does not have a significant impact on pregnancy, which is mainly due to the risk of rheumatoid arthritis involving the kidneys and other important organs and the danger is very small, which is also the difference between it and other autoimmune diseases. Third, the treatment of rheumatoid arthritis in pregnancy Commonly used therapeutic drugs are non-steroidal anti-inflammatory drugs, glucocorticoids, gold agents and immunosuppressive agents. NSAIDs include aspirin, indomethacin, etc., which can produce side effects such as overdue pregnancy, premature closure of the ductus arteriosus (avoiding application in late pregnancy), and oligohydramnios; glucocorticoids are mainly applied for a short period of time to control the symptoms; the teratogenic effect of gold agents is unknown, and should be avoided as much as possible during pregnancy; immunosuppressants, such as azathioprine, CTX, and MTX, etc., can lead to fetal abnormalities, and should be avoided during pregnancy as well. Immunosuppressants such as azathioprine, CTX and MTX can also cause fetal malformations and should be avoided in pregnancy.