In a Facebook post, Melanie Tan Pelaez posted a picture of her red, blistered arm and issued a warning to others to keep their phones well away from their beds.

"I recently purchased an Apple iPhone 7 and accidentally fell asleep with my arm on my phone whilst it was charging. I was woken up by sudden pain, pins and needles, numbness and shortness of breath" reads the post.

"I have been an iPhone user since the beginning and have never had an issue or concern, so it's really scary and disappointing that something like this happened and can happen to someone else".

Fortunately, she was apparently otherwise unharmed.

Ms Pelaez, who is 15 weeks pregnant, told Fairfax Media she fell asleep watching movies on her phone last month and woke up in pain.

At first, she wasn't sure what had caused the injury.

"I woke up with pins and needles radiating from the bottom to the top [of my arm]," she said. "I thought it was something wrong with me medically."

Ms Pelaez went to a hospital emergency department where they ran tests on her heart and blood. Doctors said she had been burnt by a foreign object and advised her to check her bed to see what had caused it. She and her husband then matched the markings on her arm to her phone and charger.

Ms Pelaez took the phone to an Apple store.

"Their first reaction was 'there is no way the phone could have done this to you'," she said.

As the days went by, with no action from Apple, the pain on the Pelaez's arm become more and more severe and the mark more distinctive.

After contacting Apple's "executive team" through their website, Ms Pelaez's phone was flown to the US for testing.

Ms Pelaez continued to see her GP and a plastic surgeon to address scarring as three weeks went by without hearing from Apple.

When she eventually emailed them, she was told the investigation would take more time to complete.

"I thought this is ridiculous," Pelaez said. "I was really frustrated that I wasn't getting any response from Apple."

It was then that she took the step of writing the Facebook post, which has since been shared more than 450 times, to warn her friends and family. She said she did not expect it to go viral.

After media outlets picked up the story, Apple got in contact to ask how she was, but they still couldn't provide any answers.

"I think it's really poor considering billions of people use iPhones," she said. "Surely three weeks is enough time to investigate one particular iPhone."

Meanwhile, Ms Pelaez is still paying for the phone under her mobile plan. Her telecommunications provider, Optus, said it could not cancel her plan until receiving the phone, which is still in the US. Apple has offered her a replacement phone, but she's refused to take one.

While handling or sleeping with a charging phone is not generally advisable — in fact Apple says so explicitly in its iPhone user guide — no reasonable user would expect the device to get so hot as to burn them. iPhones — and other smartphones besides — will shut off automatically if they overheat, due to being confined or being exposed to direct sunlight or another heat source.

Apple's advice in its iPhone user guide. It's clear the company knows prolonged contact with a charging iPhone is a danger.

If the iPhone was to blame for Pelaez's injury, it's unclear whether or not there was some kind of malfunction or other factors.

Apple has not made an official statement on the matter.