The National Blood Service (NBS) has rejected claims that ejaculation during sexual activity causes men to lose significant amounts of blood.
According to a report by myjoyonline.com, the Service issued the clarification on August 20, 2026, describing the claim as scientifically inaccurate.
The statement was issued in response to comments by the Chief Executive Officer of Chartma Herbal Health Centre, Dr Charity Twumasi, who claimed that a single ejaculation releases “400 million cells” and equated the volume of semen to “one pint of blood”.
She also suggested that frequent sexual activity could result in dangerous blood loss.
The National Blood Service, however, said the assertion was false and could mislead the public about blood donation, sexual health and other medical conditions.
“No Circulatory Depletion: Blood is contained strictly within the circulatory system. Ejaculation does not deplete, draw from, or impact systemic blood volume. Standard sexual activity causes absolutely zero blood loss,” the Service stated.
The NBS further rejected any comparison between the volume of semen released during ejaculation and the amount of blood contained in a pint.
It explained that although semen contains millions of microscopic sperm cells, the overall volume of seminal fluid is normally about 2 to 5 millilitres.
This is significantly lower than a pint of blood, which is approximately 473 millilitres.
The Service therefore stressed that ejaculation does not result in the kind of blood loss suggested by the claims.
It also warned that spreading scientifically inaccurate information could have broader public health consequences by confusing people about how blood is lost, replenished and donated.
The NBS urged the public to rely on medically established information and avoid sharing claims that could undermine understanding of sexual health or discourage voluntary blood donation.
