Enable has suffered a setback in training but is expected to be able to defend the Prix de l'Arc de Triomphe.
Trained by John Gosden, Enable won six of her seven starts in 2017 including five consecutive Group One races.
She has not been seen since she won the Arc at Chantilly in October and had been pencilled in to make her reappearance in the Coronation Cup at Epsom on June 1.
But she will now miss the first part of the season through injury.
"Enable has met with a setback in training. She has some filling in her knee which is being fully investigated," Teddy Grimthorpe, racing manager to owner Khalid Abdullah, said in a statement.
"The advice that we have is, that given reasonable circumstances, she should be ready to run in August as a preparation for the Prix de l'Arc de Triomphe."
Having burst on to the scene at Epsom with her five-length win in the Oaks, Enable repeated the dose in the Irish Oaks.
Connections then took the bold step to run her against the older colts in the King George VI And Queen Elizabeth Stakes and they were dealt with in much the same way.
Group One winners like Ulysses and Highland Reel did not see which way she went and officials at Ascot would no doubt have been hoping she would grace the race again in July.
A clash with stablemate Cracksman would have been one for the ages, with Frankie Dettori already agonising over the decision of which superstar to ride. Now he will have until October to choose.