France's first lady Valérie Trierweiler has been hospitalised suffering from stress after she learned of President François Hollande's alleged affair with an actress, her office said, The Telegraph reported.
The 48-year-old journalist was admitted to a Paris hospital on Friday shortly after she heard of the allegations in a gossip magazine that her boyfriend had been spending nights in an apartment near the Elysee palace with actress Julie Gayet.
Her office, confirming press reports, said she had gone into hospital to "get some rest and have some tests done" and would be discharged on Monday.
Mr Hollande, 59, has threatened to sue Closer magazine for breach of privacy but he has not denied the affair.
Trierweiler, a journalist for the celebrity magazine Paris Match for whom Mr Hollande left fellow Socialist politician Ségolène Royal, the mother of his four children, has made no comment since the story broke.
All eyes are on the president's traditional start of the year press conference on Tuesday to hear what he might have to say about the alleged affair and what it means for his relationship with his unmarried partner who has been dubbed France's "First Girlfriend".
If he announces it is over with she would have to leave the Elysee, where she has an office and a staff of five working for her.
If he does not she would still be in the embarrassing situation of having to put a brave face on it as France snickers about her boyfriend's alleged antics.
"Is it normal that she stays at the Elysee at taxpayers' expense while the president has other relationships?" asked opposition UMP party deputy Daniel Fasquelle, a rare exception to the wave of support Mr Hollande has received from political friends and foes alike who profess to be outraged at the invasion of his privacy.
"The French may ask themselves the question: who is now the first lady of France?" Mr Fasquelle tweeted.
The conference is one of the rare occasions when a French president subjects himself to a prolonged grilling by the media. In 2008 it was used by the recently divorced then president Nicolas Sarkozy to announce that with his new love, ex-supermodel Carla Bruni, "it's serious".
Though many French have been fascinated by the romantic intrigue in the Elysee, an opinion poll on Sunday showed that a clear majority think the president's love life is not an issue of public concern.
The survey by IFOP said 77 per cent of voters believe the alleged affair Miss Gayet revealed by a gossip magazine was a private matter.
Eighty-four percent said it would not change their opinion of the leader whose failure to turn around the ailing economy and bring down stubbornly high unemployment has made him the most unloved French president in modern history.
"He is so unpopular that it hasn't changed a thing," Frederic Dabi of IFOP told the Journal du Dimanche, the paper that commissioned the poll which confirmed France's famed tolerance towards the colourful love lives of its leaders.
Miss Royal on Sunday refused to comment on the alleged affair, saying she did not want to fuel the debate on "a soap opera that is very far from the concerns of the French".
"We must turn the page and get back to work," she told France 2 television.