You can go for an ultrasound after 40 days in the first trimester. You can go for the corresponding examination after 42 days in the first trimester, and in addition to the more routine examinations, you can check whether the pregnancy is normal through ultrasound, and at this time you can determine whether there is a possibility of ectopic pregnancy. This is why it is important to go for an ultrasound in the early stages of pregnancy to determine whether the pregnancy is normal or not. You can also go for an ultrasound around 112 days of pregnancy to be able to specifically observe and know if the fetus is developing normally. Pregnant women do not need to have an empty stomach when they go for an ultrasound, but they should try to wear loose and easy to take off clothes before going for the test. In early pregnancy, you need to hold your urine for the ultrasound to see clearly, but you should not eat foods that produce gas easily, such as sweet potatoes.