Pregnancy is a delicate time in the life of a woman. In the past, when medical science was not very advanced, there were a lot of health issues faced by both the pregnant woman and her unborn child. There was not much anyone could do to predict any problems that might arise in pregnancies. Because of this, the causes of many of the pregnancy complications remained unclear. But, today that is not the case. Medical technology has advanced a lot enabling prompt diagnosis of any problems leading to a higher chance of the mother and the child remaining unharmed. One of the new technologies used to ensure the proper and healthy growth of the unborn child is the ultrasound.The ultrasound is a medical imaging technique used to view the inside of your body. During pregnancy it is used to check the foetus as it grows inside the uterus. From the image created, the doctor will be able to govern the growth of the baby, any unusual developments and even help to predict the date of delivery.In this article we may discuss how does ultrasound work in pregnancy. We may also see if ultrasound is good or bad for the baby. When to have ultrasound: Ultrasound is a medical imaging technology and as such should be performed only if prescribed by your gynaecologist. This is in response to whether ultrasound is good or bad for the baby.Sound waves: The ultrasound machine transmits high frequency sound waves into the body, which when reflected back gives us the image of the growing child. Since sound waves are used there is no question of whether ultrasound good or bad for the baby.No radiation: Another notable feature of this technology is that it uses no radiation to procure the internal image of the foetus. So, there is no need to worry whether ultrasound is good or bad for the baby.Abdominal ultrasound: This is the type of ultrasound, which is normally practiced to see inside the womb of a pregnant woman. You can ask your doctor to explain how does ultrasound work in pregnancy, if you have any doubts.Vaginal ultrasound: This is a type of ultrasound recommended for women who require ultrasound very early in their pregnancy. Here, the probe is placed into the vagina. Knowing the technique will help you know how does ultrasound work in pregnancy.3D ultrasound: This is a recent development in ultrasound imaging. Previously we used to get two dimensional images of the foetus, but here, we will see the image in 3D.Doppler ultrasound: To know how does ultrasound work in pregnancy in this particular type we need to have an understanding of Doppler Effect on which this is based. This is used to understand movement inside the body.Dangers of ultrasound: We have seen how does ultrasound work in pregnancy, but we also need to be aware of a few of its dangers. Two major dangers are the development of heat and formation of bubbles or cavitations.Regulations on ultrasound: While discussing how does ultrasound work in pregnancy we also need to know about the regulations on this technology in many countries. Without a medical reason it is not allowed to conduct an ultrasound.