One woman in China has made headlines after she woke up one morning and noticed that she was suddenly unable to hear male voices. The strange problem first became apparent when she realized she could not hear her boyfriend speak. 

Though bizarre, a female doctor at Qianpu Hospital examined the patient — only identified by her last name Chen — and seemed to have it figured out.

"She was able to hear me when I spoke to her, but when a young male patient walked in, she couldn’t hear him at all," said Dr. Lin Xiaoqing, an ear, nose, and throat specialist at the hospital.

She diagnosed Chen with a rare condition known as reverse-slope hearing loss. People who are affected by this typically have no problem hearing high-frequency sounds such as the voices of women and children.

But they find it difficult to hear lower frequencies — like male voices which tend to be deep more often than not. They may also struggle to hear the sounds of vehicles, thunder, voices over the phone, the humming of refrigerators, etc.

RSHL is very rare, which you may have guessed from the unusual headline. It is estimated to have affected around 3,000 people in the United States and Canada — which would mean only one case of RSHL for every 12,000 cases of hearing loss. 

Genetics may play a role as RSHL could be inherited through a dominant gene. Certain diseases and infections, especially severe ones that occur during childhood, have been suspected to trigger the hearing loss. Changing pressure of a fluid in the inner ear has also been identified as a possible cause.

But there are some cases where the hearing loss has been linked to a lack of sleep or high levels of physical stress. Dr. Xiaoqing believes this is likely what happened with Chen who admitted that she was working really long hours and not taking enough care of herself.

The night before her hearing loss set in, she experienced symptoms like a ringing sound in her ears as well as nausea. Chen is now receiving treatment and is expected to make a full recovery.

If you suspect that you have a similar hearing problem, you can see an audiologist who will conduct a series of tests. While it can significantly improve your listening experience with music, safety is the main reason why you should not skip on diagnosis and treatment.

"Much of what you lose with RSHL is environmental sound," Audiology Hears stated. "If you can’t hear a car coming, you can’t avoid it. If someone some distance from you is trying to warn you away from something, you might not hear it, because volume is a product of the lower frequencies."