The kidneys largely return to their pre-pregnancy levels about six months after delivery. Very few patients may have permanent kidney damage, but the vast majority are able to heal on their own. If a patient originally had chronic nephritis and the nephritis worsened after pregnancy, the nephritis may improve after the end of pregnancy; some patients do not need pharmacological intervention before pregnancy and subsequently need pharmacological intervention after pregnancy because of the increased burden on the kidneys. If no kidney disease was found before pregnancy, but after pregnancy, kidney disease is suddenly found, resulting in failure to restore kidney function, kidney puncture may be required to determine the cause, and certain treatment will be given according to the results of kidney pathology. For example, IgA nephropathy in chronic nephritis may progress through pregnancy strike or after the burden of pregnancy is increased. Another condition is SLE. Maybe some patients were quiescent before pregnancy or did not know they had SLE before pregnancy, and after pregnancy, due to the effect of estrogen, the lupus activity relapsed. In this case, after termination of pregnancy in some patients, the lupus activity will slightly improve, but still need renal puncture or symptomatic treatment, and the kidney condition will be relieved to some extent.