Norway's Crown Princess Mette-Marit will likely need a lung transplant as her health has worsened in recent months, the country's royal household has said.

The princess, 52, was diagnosed with pulmonary fibrosis in 2018. The degenerative disease creates scar tissue that stiffens the lungs making it difficult to breathe and for oxygen to enter the bloodstream.

Tests in autumn showed a clear worsening of her health, the palace said on Friday. We are reaching the point where a lung transplant will be necessary, Are Martin Holm, head of respiratory medicine at Oslo University Hospital, said.

Princess Mette-Marit told public broadcaster NRK that her illness had developed faster than I'd hoped.

No decision has been taken yet on whether she will be placed on the transplant waiting list, Dr. Holm said. The palace noted that her doctors had started the evaluation process for lung transplant surgery.

In Norway, there are usually between 20 and 40 patients on the waiting list for a lung transplant, and Princess Mette-Marit will not receive preferential treatment if she is placed on the list.

Although she is not yet on a donor list, Dr. Holm emphasized that her healthcare team is preparing for a future transplant when necessary.

The palace mentioned that Princess Mette-Marit has an increasing need for rest and tailored exercise. Nevertheless, she remains committed to her royal duties, with adjustments to her engagements being made to accommodate her health issues.

Dr. Holm characterized pulmonary fibrosis as a dangerous disease that can manifest inconsistently, with individuals appearing healthy at rest but struggling during physical exertion.

Princess Mette-Marit's husband, Prince Haakon, noted she may seem perfectly fine while sitting still but has been struggling more with breathing and energy levels.

Hiking or skiing—activities the couple used to enjoy—are no longer feasible, Prince Haakon explained. The prospect of a transplant has been daunting for Mette-Marit, who is aware of the associated risks.

A successful transplant depends on finding an appropriate match and preventing the body from rejecting the new organ. Dr. Holm clarified that transplants are considered a last resort for patients facing significant illness and limited life expectancy.

News of the princess’ declining health follows the recent legal troubles of her eldest son, Marius Borg Høiby, who is set to face trial on several serious charges.