A gestational sac at 9 weeks being 0.8 centimeters away from the cesarean section means that the distance between the gestational sac and the cesarean section scar at the time of the ultrasound examination is 0.8 centimeters. Regular medical checkups are needed during pregnancy. If the first child was born by cesarean section, the location of the gestational sac needs to be known during the second pregnancy. If it is farther away from the cesarean section scar, it will not usually cause irritation at the scar, resulting in a scarred pregnancy. If it is closer to the C-section scar, there is a risk of scar pregnancy and bleeding at a later stage. During pregnancy, you need to pay more attention to your health, and if you notice any abnormal symptoms, you are advised to consult a doctor. Regular medical checkups are also needed, and it is best to avoid strenuous exercise.