MONCTON, N.B. - As Paula and Martin Theriault stare wide-eyed at the flat-screen TV, a clearly detailed, full-motion image of their unborn daughter leaves them breathless.

"Wow, it was pretty exciting, just seeing the face," Paula Theriault says as an ultrasound technician with Baby Images Inc. moves a small scanning device across her round belly.

"You can really see the details of the eyes, the face, the nose ... you can see her move."

The couple from Dieppe, N.B., have come to the new private clinic in Moncton to determine the sex of their child and purchase pictures and high-resolution video recordings - services most hospitals won't provide.

Private, for-profit ultrasound clinics are popping up across Canada - another chain, UC Baby of Mississauga, Ont., has expanded to 16 locations in five years - even though Health Canada has issued warnings about the potential health risks associated with exposure to ultrasound for non-diagnostic purposes.

The federal department has established guidelines that state ultrasound images should not be used for non-medical reasons or for commercial purposes.

Ultrasound is a non-invasive technique that uses high-frequency sound waves to create images on a monitor of internal soft tissues and body cavities, such as a fetus growing in the womb.

"There really has been no proven harm, but when you put energy into tissue, there is a certain amount of heat that is generated, and whether that has any potential ill effect - who knows?" says Dr. Andrew Ross, past president of the Nova Scotia Association of Radiologists.

But the federal warnings mean little because the regulation of ultrasound clinics is under provincial jurisdiction.

"It's an uncontrolled environment in terms of any kinds of regulations - timing, power, all those sorts of things," says Ross. "That's why all the professional associations are all very adamantly opposed to this type of utilization of what is considered a medical device for non-medical purpose."

The fact that many hospitals won't reveal the sex of a fetus is probably driving business to private clinics, Ross says.

Ultrasounds in hospitals are typically done early in the pregnancy when it is tough to determine the sex, but the private clinics offer the service much later in the pregnancy.

UC Baby won't use its equipment to determine the sex until the fetus is at least 22 weeks old. Baby Images in Moncton sets the limit at 20 weeks.

Paula Theriault, who is expecting in November, says she just had to know whether she was having a boy or a girl.

"We wanted to know ... to be ready, the room, and just to be set," she says.

Linda Richard, owner and operator of Baby Images, says parents also want to be reassured that everything is fine with the fetus.

"People like to see five fingers and toes or check for cleft palates ... make sure everything is there," she says.

Her Moncton facility features soft lighting, soothing music and large leather couches for friends and family members to be part of the session, which lasts at least 30 minutes.

On its website, Baby Images promises clients a sneak peak of the future:

"Yawning? Stretching? Sucking her thumb already? Playing with his toes? See the unbelievable! Now you can experience the wonder of 3-D and 4-D ultrasound and get a glimpse of the new person who will soon be entering your life!"

Richard, who is also a registered nurse at a Moncton hospital, says despite the warnings, she believes the technology is safe.

"There is nothing that shows in 40 years of studies that it's harmful to the fetus or the mom," she says. "But just to be on the safe side, I suppose Health Canada put that (warning) out."

Tina Ureten started UC Baby in Mississauga in 2003. The chain now has locations in six provinces.

Trained as a radiologist in Turkey, Ureten says private ultrasound services are operating around the world, and she thinks the concerns in Canada are more about politics than safety.

"There's no involvement of the medical professionals, and patients can decide for themselves," she says. "There's no doctor making any benefit from this service."

The cost of the service isn't cheap, ranging from about $100 for basic photos to $300 for deluxe video packages.

For Tanya Campbell of Tantalon, N.S., who is expecting in November, it was the high cost that kept her from booking a session - not the warning from her doctors.

Campbell, the mother of a two-year-old son, says she was unaware Health Canada or the U.S. Food and Drug Administration had issued warnings about the practice.

The fact that many people are unaware of the warnings is a concern for Jan Gilby, president of the Nova Scotia Society of Diagnostic Medical Sonographers.

"People are not making an informed and educated decision to go to these clinics," Gilby says.

"When you are exposing a fetus for 30 minutes just to get a 3-D picture or to get a videotape, or to determine gender, just for entertainment purposes, I have some concern over that conflicting with everything that I've been taught."