MI and TI displayed in ultrasound are two parameters in the diagnostic ultrasound machine, MI refers to the mechanical index and TI refers to the thermal index, and both parameters need to be adjusted for doing routine ultrasound examinations. In general, especially for the examination of pregnant women, these two parameters must be adjusted so that they are within 1.0 to be safe. Because in early pregnancy, especially in the first trimester, the fetus’ nervous system and eyes are just starting to develop, sometimes a high level of these two indices can have an impact on the child’s eye or nervous system development. Therefore, it is important to adjust these two parameters to within the normal range during the obstetric examination in early, middle or late pregnancy.