Leslie Sinclair has donated 125 pints of blood over the course of nearly 50 years.
However, he was turned away on his most recent trip after refusing to answer a question about whether or not he was pregnant.
Mr Sinclair, 66, was asked to complete a form that inquired if he was pregnant or had been pregnant in the previous six months.
Mr Sinclair claimed that when he complained that as a man in his 60s, this question did not relate to him and that he should not have to answer it, employees at the clinic told him that his blood could not be accepted.
The standoff occurred as NHS England began a push earlier this week to recruit a million additional blood donors over the next five years, following the pandemic’s drop in numbers.
The Scottish National Blood Transfusion Service (SNBTS) launched a search for 16,000 new donors earlier this month.
Last night, it was revealed that all potential donors are asked if they are pregnant in order to ‘promote inclusiveness’ and because pregnancy isn’t usually visible.
Mr Sinclair walked away, enraged by the refusal to take his blood, and expressed his displeasure with the ‘nonsensical’ decision yesterday night.
The father of two, from Stirling in central Scotland, said: ‘I am angry because I have been giving blood since I was 18 and have regularly gone along. I’m very happy to do so without any problem.
‘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.
‘I pointed out to the staff that it was impossible for me to be in that position but I was told that I would need to answer, otherwise I couldn’t give blood.
‘I told them that was stupid and that if I had to leave, I wouldn’t be back, and that was it, I got on my bike and cycled away.
‘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.’
‘She just can’t understand it either,’ said Mr Sinclair, referring to his 59-year-old wife Margaret. Donors must wait six months after giving birth to donate blood if they are pregnant.
On Wednesday, Mr Sinclair, a retired driver for an engineering firm, went to the Albert Halls in Stirling to donate blood.
Last night 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.’