Having a fetal ultrasound (aka sonogram) is arguably the most exciting medical appointment for expectant parents, given that the procedure offers them the earliest peek at their new baby. Obstetricians generally order a routine ultrasound at least twice during a woman’s pregnancy to monitor a developing fetus and look for signs of complications.

But a growing number of commercial ultrasound businesses or “sonogram studios” have emerged in shopping centers nationwide just to keep up with the demand of parents wanting to see their unborn baby in action. The Food and Drug Administration (FDA) warns these so-called “keepsake” ultrasounds have no medical benefit, and that undergoing ultrasounds when it is not medically necessary may carry some serious risks.

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What’s the danger?

Ultrasounds use high-frequency sound waves that penetrate the mother’s body tissues. The high-energy vibrations then bounce back to form moving images of the baby in the womb on a screen for parents to see.

The energy from the sound waves is not ionizing (meaning it will not remove electrons from atoms or cause atoms to become charged), so ultrasounds are safer than other forms of imaging like X-rays or CT scans, according to James Brink, MD, chief of radiology at Brigham and Women’s Hospital in Boston. However, Brink says, that doesn’t mean ultrasounds should be used more frequently or for the purpose of a fun photo shoot. “The risks are more theoretical than documented, but the potential risk is still there,” Brink says, adding that it is difficult to study the risk of prolonged ultrasounds to an unborn fetus.

Shahram Vaezy, a biomedical engineer for the FDA, said in a December 2014 public statement, "Ultrasound can heat tissues slightly, and in some cases, it can also produce very small bubbles in some tissues."

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In some cases, businesses looking to capitalize on parents’ eagerness use the machines for up to an hour to produce a take-home video. “It just doesn’t seem prudent to expose a fetus to more energy than it should [be exposed to],” says Brink.

Brink, who helped push Connecticut legislation banning keepsake sonograms in 2009, says the largest concern about businesses that offer commercial ultrasound is the equipment not being regulated or controlled. Also, technicians conducting the ultrasound may not be properly trained. “These folks may not be qualified to use the equipment properly, purchase appropriate equipment or give medical diagnosis or advice,” he says.

Indeed, the FDA and the American Institute of Ultrasound in Medicine advise that ultrasounds be requested by a physician for medical purposes and performed by professionals trained to recognize medical conditions and potential problems with the fetus. Those professionals also know techniques to avoid ultrasound exposure beyond what is considered safe.

Like Brink, medical experts nationwide have long been voicing their opposition to sonograms for entertainment purposes. In 2005, actor Tom Cruise revealed he bought an ultrasound machine to check in on his daughter with then-pregnant actress Katie Holmes. In 2006, California passed the “Tom Cruise Law” banning the sale of ultrasounds in the state to anyone other than licensed clinicians.

The American Medical Association, the American College of Obstetricians and Gynecologists, the American College of Radiology and the American Pregnancy Association also have come out against the practice.

Many obstetricians understand parents’ interest in watching their forming baby and would be happy to share in the excitement, Brink says. “Most practicing accredited clinics will give ultrasound photos to parents during medical procedures,” he adds, if they just ask.

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Lara Salahi is a multimedia journalist who specializes in health and medical news.