Meghan, 21, said in a message to fans via Instagram that she haemorrhaged her vocal chord once again.
She said: "I have hemorrhaged my vocal cord again. I got bronchitis & have been coughing a lot & that pushed it over the edge. Sadly, I will need to cancel the remainder of my tour and get surgery to finally fix this once and for all."
Meghan, who had to cancel some dates in July due to vocal chord issues, told fans she was "devastated, scared and so sorry".
'All About That Bass' hitmaker Meghan was due to continue her 'MTrain Tour' into September.
Meghan, whose debut album Title went to Number 1 in the UK music charts earlier this year, added: "I am determined to do what it takes to get better and come back around stronger than ever."
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