More than half of trans women who have ‘bottom’ surgery are in so much pain years later they need medical attention, a study suggests.

Up to a third of patients also struggled to use the toilet or suffered sexual issues 12 months after the operation, which sees patients transitioning from male to female given a surgically constructed vagina.

Researchers from the Women’s College Hospital (WCH) in Ontario, Canada, analyzed the medical records of 80 patients who sought care from the clinic between three months and five years after having the operation.

Campaigners say the findings demonstrate that complex surgeries like vaginoplasty often carry risks that patients are unaware of – at a time when there has been a dramatic uptick in the number of gender reconstruction surgeries in the US and Canada.