Baby monitors‚ popular among parents‚ have no proven benefits for healthy infants‚ a new US study shows.

The researchers evaluated five consumer-grade monitors‚ similar to those sold in South Africa‚ and found “no evidence that these devices were safe‚ accurate or effective”.

Typically these electronic sensors monitor vital signs and alert parents on their smartphones to changes‚ for example‚ in breathing.

Instead of delivering peace of mind‚ Dr Christopher Bonafide‚ paediatrician and safety expert‚ warned that baby monitors might raise undue alarm in parents.

“These products may cause unnecessary fear‚ uncertainty and self-doubt in parents‚” said Bonafide‚ who is based at the Children’s Hospital of Philadelphia.

Many monitors on the shelves of baby stores have not been tested for safety and quality‚ nor approved by a regulatory authority like the Federal Drug Administration in the US.

The SA invention the Snuza Hero‚ however‚ was the first portable baby breathing monitor to be medically certified to European standards and has won major awards.

Snuza co-owner and design engineer Greg Gallagher said they have sold more than 350‚000 units worldwide and had not a single SIDS (sudden infant death syndrome) death.

“We have dozens of testimonials from parents to say they were alerted to their babies stopping breathing and took action. The Snuza is clinically proven to detect apnea‚” he said.

Gallagher claimed that according to their surveillance‚ they had the lowest false alarm rate of all devices on the market.

Megan Faure‚ infant specialist and co-author of the best-selling manual Baby Sense: Understanding Your Baby’s Secret World‚ said a proven baby monitor might be useful to parents whose babies had previously had medical problems.

But research indicated that ordinary baby monitors could disturb the sleep of babies and sleep among parents who used them‚ she said.

“They play on the parents’ anxiety and worst nightmare‚ SIDS‚ which parents can’t control for. The alerts can create more anxiety and parents become hyper-responsive‚” said Faure‚ who is based in Cape Town.

That worries Bonafide too. He said‚ for example‚ one low oxygen saturation reading‚ which could settle on its own‚ might trigger a visit to an emergency department‚ followed by unnecessary blood tests‚ X-rays and even hospital admission.

Bonafide evaluated five models with his colleagues from the nonprofit ECRI Institute‚ which researches medical devices‚ procedures and processes.

The models included MonBaby‚ Baby Vida and Owlet which have been available for the past two years and cost from $150 to $300 (about R2‚000 to R4‚000) and found “nothing to prove they were life-saving or accurate”.

American neonatologist Elizabeth Foglia‚ who looks after infants in the intensive care unit‚ said parents often asked if they should use an apnea monitor when their babies first came home.

“In the future‚ some physiological monitors may offer real benefits to vulnerable infants at home‚ but we have no evidence now that these devices are safe‚ accurate or effective‚” she concluded.