1. What Is An Sonogram?
    Sonograms, also called ultrasounds, refer to high frequency sound waves. When these sound waves hit a dense mass, tissue or fluid, they produce echoes, which bounce back to a receiver. The receiver then translates these into a signal that converts to either sound (fetal heartbeat) or an image.
    Ultrasound technology is used during pregnancy for the familiar fetal “scan”, to listen to the baby’s heartbeat (Doppler) and for electronic fetal monitoring during labor.
    The most common reasons it is used are:
    Confirming a pregnancy and checking for twins or more
    Estimating gestational age
    Checking fetal growth
    Checking the well being of the baby – including blood flow to and from the placenta, as well as how much amniotic fluid is around the baby.
    Diagnosing a miscarriage, bleeding and fetal or placental abnormalities.
    Confirming the position of the baby for procedures such as an amniocentesis or turning the baby from a breech position to head down (external cephalic version).

    Are They Safe?
    It has been over 40 years since ultrasound was first used on pregnant women. Although some harmful effects in cells have been observed in a laboratory setting, abnormalities in embryos and the offspring of animals and humans have not been demonstrated.

    Apparent ill effects such as low birth weight, speech and hearing problems, brain damage and non-right-handedness reported in small studies have not been confirmed or substantiated in larger studies from Europe. The studies were not adequately performed or large enough to show actual validity.

    Of course, it remains important for scientists to continue to study the effects of this technology. Ultrasounds are considered to be a very safe method of providing valuable information during pregnancy. There is no indication that they are harmful or affect the baby in any way.
    In some areas, women can even choose to see their babies in 3-D or 4-D color scans. Sometimes these sonograms are offered in non-medical settings that are set up very much like photography studios. Personally and professionally, I have mixed feelings about having an ultrasound merely for a photo or video of the baby. I think it is sensible to have one only as needed, and recommended by your care provider.

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Ask Tori RN®, by registered nurse and resident author of The Joy of Pregnancy, is a helpful and reassuring resource for parents-to-be.