Glenn Ketchen's testosterone implant, December 2000.
© Science Museum / Science & Society Picture Library
Glenn Ketchen took part in a trial of the male pill and testosterone replacement implants at Edinburgh University during 1998 and 1999. A pill was taken daily and stopped the production of sperm and testosterone, so a testosterone implant was used to replace it. Ketchen's was the first succesful trial of a male pill in which all participants' sperm counts were reduced below fertility levels without any significant short-term side effects.