A furious man left a blood donation centre and refuses to go back after being asked if he was pregnant.
Leslie Sinclair, from Stirling, was asked if he was pregnant on a medical form and says he won't go back until the question is scrapped.
The 66-year-old has donated 125 pints of blood in almost 50 years, but now says he never will again unless he's allowed to skip the "stupid" question.
However, the head of the Scottish National Blood Transfusion Service (SNBTS) explained all donors are now asked the same questions to make everyone feel included and stop discrimination.
Mr Sinclair, who has been giving blood since he was 18, says he's angry because there is no need for him to answer the question but staff told him he needed to, the Scottish Daily Mail reports.
The question asked whether he was expecting a child or had been pregnant in the past six months.
Pregnant women must wait six months after giving birth to donate blood.
The retired driver, from Stirling, Scotland, told them it was "stupid" and "got on [his] bike and cycled away" after going to the centre at Albert Halls on Wednesday.
He said: "There is always a form to fill in and that's fine - they tend to ask about medical conditions or diseases - and clearly that's because the blood needs to be safe.
"This time around, there was a question I hadn't seen before: 'Are you pregnant, or have you been in the last six months?' which required a yes or no answer.
"It is nonsensical and it makes me angry because there are vulnerable people waiting for blood, including children, and in desperate need of help.
"But they've been denied my blood because of the obligation to answer a question that can't possibly be answered."
He added that his wife, 59-year-old Margaret, agreed with his actions.
NHS England wants to recruit a million more blood donors over the next five years after numbers fell during the pandemic.
The SNBTS wants to find 16,000 in the next year.
Professor Marc Turner, director of SNBTS, said: "We appreciate the support of each and every one of our donor community and thank Mr Sinclair for his commitment over a long number of years.
"Whilst pregnancy is only a relevant question to those whose biological sex or sex assigned at birth is female, sex assigned at birth is not always visually clear to staff.
"As a public body we take cognisance of changes in society around how such questions may be asked without discrimination and have a duty to promote inclusiveness – therefore all donors are now asked the same questions."