The cost as much as $85 a session and are billed as the perfect way to pamper your infant, but two experts have warned about the dangers of baby spa flotation devices.
The international groups have now come forward and warned parents against putting their babies in the devices because of the "damaging" effects they could have on emotional, neurological and physical development.
Founder of Birthlight, Francoise Freedman said in the 'Hidden Risks of Floating Neck Rings For Babies' report that frequent use of the neck floatation rings may have "long-term implications".
"When babies hang vertically in water with their heads supported by a semi-rigid foam structure – particularly those under five months – concern arises about compression of the soft and subtle vertebrae in their necks, and strain in ligaments and muscles.
"Infant development proceeds from the head down and head control is the first huge task babies master in their early months, followed by rolling.
"The main body movements that help babies to achieve these first milestones are restricted by neck rings."
She also warned that for babies over the age of three months, regular use of the rings could impact on their ability to sit up.
"It takes a disproportionate effort and muscular tension for babies in neck rings to try and right themselves up, which they are naturally driven to do," she said in the report.
"Neck rings make babies passive rather than enabling them to physically tale advantage of challenges and opportunities while being in the water."
Co-author of the report, Shawn Tomlinson from the Swimming Teachers' Association (STA) said babies' body movements are restricted when using the rings.
"A neck ring creates a vacuum when the baby is incapacitated and cannot connect with anyone or anything," he said.
"There are no safe boundaries (for babies) to touch or feel.
"Self-expression through body language, which the water ideally facilitates, is lost because movements are restricted."
STA's aquatics manager Kayle Burgham said while the rings look relaxing for babies – they are not.
"While disengaging from the world in floating tanks can be wonderfully relaxing for stressed adults, this is not what babies want or need – physically or emotionally," she said.
This isolated activity goes against the very essence of baby swimming, which is human contact: bonding with your child so they can explore the water in a safe, relaxed, fun environment."