Cellist Katherine Jenkinson, 34, was booked to play at the Oriental Club in central London with her chamber group.
"Very upsetting, insensitive and quite frankly rude"
But, when she asked if her babysitter could care for her 11-weeek-old daughter in the dressing room while she played, she was told it would not be allowed.
Katherine, who is currently breastfeeding baby Olivia, could think of no other solution than to have the babysitter wait outside in a car with the newborn.
During the interval, Katherine popped out to breastfeed her baby girl.
She told The Telegraph: “I'd already arranged a second babysitter to be at home with my 4 year old son as I'm fully aware that it is often inappropriate to take children to such events.
“Does this really apply to a breastfed 11-week-old babe in arms?"
"I found the way they handled the whole situation very upsetting, insensitive and quite frankly rude.”
While the club has yet to respond to request for comments, some have suggested that Katherine should have left the newborn at home and expressed milk for her.
What do you think - should the club have allowed the newborn baby to stay in the dressing room? Let us know via the poll below.