Pregnant women need to have an ultrasound after their pregnancy is confirmed. The main purpose of ultrasound is to determine the size and location of the gestational sac, to understand the viability of the embryo, and to rule out ectopic pregnancy. In the early stages of pregnancy ultrasound is generally recommended to do vaginal ultrasound, because vaginal ultrasound than abdominal ultrasound to see more clearly, and do vaginal ultrasound than abdominal ultrasound can be seen 3-5 days earlier than the gestational sac. Vaginal ultrasound has no effect on the pregnant woman and does not increase the probability of miscarriage, so you can be assured that the test is safe.Ultrasound is a non-invasive test, the coupling agent and ultrasound detection, will not affect the development of the baby. There are many more ultrasounds that need to be done throughout the pregnancy, and the follow-up ultrasounds are usually done through the abdomen.