The Spanish aristocrat has broken her hip bone after falling at her ancestral home, Las Dueñas Palace.
Cayetana Fitz-James Stuart y Silva, 85, had to cancel a promotional event on Wednesday for her memoirs, I, Cayetana after the accident.
The head of the book's publishing company assured journalists that the duchess was well and had returned to her residence after spending the morning in hospital.go here
Doctors have ordered complete rest as she recovers.
The much-loved duchess wed civil servant Alfonso Diez – who is, at 61, 24 years her junior – on October 2.
Before settling into married life together in Las Dueñas, the couple honeymooned in France.
They were spotted taking a romantic stroll around Eugénie-les-Bains, in the Lands department in the south-west of the country.
The pair were guests at an famed spa resort owned by renowned French chef Michel Guérard.
Cayetana and her new husband also planned to celebrate their newly-married status with a Trip to Thailand, but their plans will have to wait until she has recovered.
In the meantime Alfonso continues looking for work.
"When he finds a job he likes, he will love living in Sevilla," when asked about how her husband was finding the relocation from Madrid.
"Maybe (he will work) in something to do with art, as he knows a lot about it."
The civil servant left his job in the Ministry of Employment in Madrid before the couple's wedding.
