For example, it can reveal the number of fetuses and age, size, fetal position, some birth defects, and other information vital to the health care of the pregnant woman and her baby. There are three types of ultrasound, each used during pregnancy for different purposes. The second is Doppler ultrasound, used before and during labor to provide electrical signals that are converted to audible signals of the fetal heartbeat. The third, vaginal ultrasound, can help diagnose the cause of bleeding and pain or an ectopic pregnancy, in which the fertilized egg grows outside the uterus. It can also detect some birth defects early in the pregnancy.
Prenatal care is vital to the health of both mother and baby.