How much do you know about ultrasound exams? | Fit Pregnancy

Womb With A View

Ultrasound exams are routine during pregnancy, but how much do you actually know about them? Here’s how they work and what they can tell you.


Why do some women get more ultrasounds? Women whose pregnancies are considered high-risk due to diabetes, carrying multiples or other conditions may have more frequent ultrasounds to measure the baby’s growth or assess fetal movement, tone and breathing. But some practitioners simply prefer doing additional ultrasounds for all their patients to keep tabs on the baby’s growth and development.

What happens if something suspicious is seen? In such cases, an ultrasound technician is not allowed to say anything to the patient, so try not to bombard her with questions. Typically, the doctor reviews all pictures, often in real time, and he or she will meet with you during or right after the ultrasound to discuss any findings. In larger medical centers, a genetic counselor may be immediately available to discuss issues of risk and your options if a problem is found, or you may be referred to speak to someone the next day, says Ellen Landsberger, M.D., an associate professor of obstetrics and gynecology at the Albert Einstein College of Medicine and Montefiore Medical Center in the Bronx, N.Y.

When can an ultrasound determine the baby’s sex? Depending on the fetus’s position, gender can usually be determined accurately during the anatomical survey, though sometimes it can be done earlier. Be sure to tell the ultrasonographer in advance if you don’t want to know your baby’s sex.

Do ultrasounds pose any risks to mother or baby? There are no known risks, but there’s no way to guarantee safety either. That’s why doctors are cautious about not overusing the diagnostic tool or treating it like entertainment. “We follow the safe principle of using the lowest-frequency sound waves possible,” Landsberger says. 

3 things an ultrasound can’t guarantee:

1. An accurate prediction of your baby’s birth weight Even when an ultrasound is done close to your due date, estimates of the baby’s size can be off by as much as a pound or even more.

2. That a baby will not have a birth defect The ability to detect an abnormality depends on a number of factors, including the fetus’s gestational age, size and position, the amount of amniotic fluid, the type of equipment used and the nature of the defect.

3. A complete anatomical picture of the fetus if you are obese Having excess body fat can interfere with an ultrasound’s ability to create a clear image of the baby. 

Here’s an in-depth look at the screening and diagnostic tests you might undergo, and how some real couples dealt with the decisions and emotional issues involved at


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