The NHS is urgently appealing for more men who have had coronavirus to donate blood plasma because they make better donors than women.
Since the convalescent plasma programme started, 73,369 women have offered to donate (63% of all volunteers) through the NHS Blood and Transplant (NHSBT) website, much higher than the number of men – 42,809 (37% of all volunteers).
Men are far more likely to donate a unit of plasma with a high level of antibodies, NHSBT said.
A man booked in to donate for the first time is three times more likely to give a high antibody unit of plasma than a woman.
This is partly because men are more seriously affected by Covid-19 and produce more antibodies.
But it is also due to men being more likely to have large enough blood volumes and veins to meet the donation criteria.
The antibody-rich plasma can be transfused into people who are struggling to develop their own immune response, and the antibodies could slow or stop the virus spreading.
NHSBT is taking plasma donations for its collaborations with the Recovery and Remap-Cap platform trials, with donations urgently sought ahead of any second wave this autumn.
There is said to be promising evidence for the effectiveness of convalescent plasma but patient benefit needs to be demonstrated in randomised control trials.
Dr Lise Estcourt, head of NHS Blood and Transplant’s clinical trials unit, said: “We’re not sure yet why there is an imbalance in people coming forward but we do know we need more men to offer to donate.
“Men have a special role to play in fighting this virus. Men who’ve had coronavirus are more likely to be able to save lives.
“We’re urgently asking men who’ve had confirmed coronavirus or the symptoms to offer to donate and help us be prepared for any second wave of Covid this autumn – you could save lives.”