The singer and 64-year-old pop icon had been due to commence The Celebration world tour, marking the 40th anniversary of her musical career, in Vancouver on 15 July.
But a statement from her manager, Guy Oseary, explained she has now been forced to push back the run of dates.
In a statement, Oseary wrote: “On Saturday June 24, Madonna developed a serious bacterial infection which lead [sic] to a several day stay in the ICU.
“Her health is improving, however she is still under medical care. A full recovery is expected. “At this time we will need to pause all commitments, which includes the tour.
“We will share more details with you soon as we have them, including a new start date for the tour and for rescheduled shows.”
Madonna first announced the tour in January, via a star-studded video that included Jack Black, Eric André, Lil Wayne, Diplo, and Amy Schumer – the latter of whom “dared” the singer to embark on the world tour covering four decades of her work.
The 35-date run of shows had initially scheduled one date at The O2 on Saturday 14 October, before upping the number of O2 dates to six: four between 14 and 18 October, and a further two on 5 and 6 December. Those dates now seem likely to be pushed back, along with the rest of the shows.
Madonna’s last tour came in 2020, with the Madame X shows being played in far smaller, more intimate theatres.
That tour had also caused health problems for Madonna, with the singer forced to pull out of the first London show on 27 January 2020, saying she had been “plagued” with injury since the tour began.
Madonna’s Sticky and Sweet Tour, between 2008 and 2009, remains the highest-grossing tour from a female artist.