In the beginning of the 1980s in France, a grouping of hundreds of men decided to act for male contraception research under the naming ARDECOM (Association pour la Recherche et le Développement de la COntraception Masculine). As a natural leader, Dr Roger Mieusset, an andrology specialist at a medical university unit in Toulouse, south of France, came out with a particular type of male underwear to ensure thermal male contraception. It maintains the testes inside the body for 11 to 14 hours daily in order to stop spermatogenesis thanks to body temperature. Men wore the underwears for periods up to 7 years as a natural and efficient contraception. They stopped the process when they decided to become fathers which went just fine. Their wives had normal pregnancies and gave birth to normal and cute babies.
Very recently, in 2013, Dr Mieusset published about his work in the book 'La contraception masculine'(Male contraception), ed. Springer.

Read more (French)