A summary of pregnancy-developments of patients with polycystic disease of the kidneys is presented. The polycystic disease of the kidneys is a chronic progessive affection which takes both the kidneys in almost every case. The development of this disease can be divided in four stages. During the first, asymptomatic stage there is no disturbance of the pregnancy. In the second stage at the beginning of the decrease of the kidney-function therapy in pregnancy consists in confinement to bed and usual kidney-disease-diet. When complications as chronic recurrent pyelonephritis and hypertension rise and the final stage -- renal failure -- is achieved the pregnancy has to be finished as quick as possible in the early pregnancy by interruption and in the late pregnancy by sectio cesarian. Both methods should be followed by sterilisation of the patient.