The monochorionic type of placentation in multiple pregnancy is very closely related to the high risk of poor outcomes. 73% of all cases of antenatal death are associated with monochorionic twins. Selective growth intrauterine restriction in one of the fetuses affects 12—25% of pregnant women with monochorionic twin. A CTG-monitor allows a fetus to be observed within 24 hours in order to identify changes in its cardiac performance. Objective: to evaluate the use of new technologies, such as daily CTG-monitoring for the timely diagnosis of the status of a fetus with selective growth restriction in a monochorionic twin. Subjects and methods. 28 pregnant women with monochorionic placentation and selective intrauterine growth restriction in one fetus were prospectively studied. Along with clinical examination, Doppler ultrasound was conducted in a pregnant woman; if there were negative changes, daily CTG-monitoring was carried out once every 3 days. Results. The patients were divided into 3 groups in accordance with altered blood flow in the umbilical artery: 1) 12 pregnant women with antegrade blood flow; 2) 10 without blood flow; 3) 6 with intermittent blood flow. The timing of delivery and for the development of selective intrauterine growth restriction, and perinatal outcomes varied with blood flow. Conclusion. The described diagnostic technology using the CTG-monitor can observe the status of a fetus with selective intrauterine growth restriction at the earliest gestational age (18—19 weeks), during which different treatment options become possible. The authors declare no conflicts of interest.