Norway's Crown Princess Mette-Marit, who suffers from an incurable lung illness, visited a hospital in Oslo on Thursday.
The Norwegian news agency NTB reported Mette-Marit was seen entering Oslo University Hospital in the afternoon, accompanied by her daughter, Princess Ingrid Alexandra and her husband, Crown Prince Haakon.
The three left the hospital about two-and-a-half hours later.
The reason for the hospital visit was not immediately known.
Norwegian broadcaster NRK reported that Mette-Marit, 52, was carrying an oxygen tank on her back.
Last month, Haakon cut short a trip to Japan due to his wife's health condition.
Mette-Marit suffers from severe pulmonary fibrosis and has been preparing for a possible lung transplant for several months.
According to NTB, such operations can only be performed at Oslo University Hospital. Donor lungs are in short supply, and decisions on when patients on the waiting list receive a transplant are often made at very short notice.
