But the sale and use of at-home fetal heart monitors has been on the rise, Rebecca Coombes, associate editor of BMJ, wrote in an accompanying editorial.
The devices are often sold over the Internet, making it hard for the U.K. Medicines and Healthcare Products Regulatory Agency -- which is responsible for regulating fetal monitors classified as medical devices -- to take disciplinary action.
But not all fetal heart monitors are medical-grade. Coombes said the regulated products use medical-grade ultrasound Doppler devices, which have to conform to medical standards and can cost $500 or more. But cheaper devices that do not use ultrasound retail for as little as $33.
"These are not considered medical devices," she said.
Chakladar said manufacturers and retailers have an obligation to make limitations like this "absolutely clear" to the consumer.
He also called on obstetric professionals to "educate expectant mothers about the limitations and consequences of untrained use of the devices."
