Hot baths Within a few months of daily exposure, the number of spermatozoa drops provided the temperature is higher than that of the body: 38 to 46 °C instead of 37 °C. Artificial cryptorchidism The principle of artificial cryptorchidism or male thermal<unk>  with testicle lifting is simple. Warming the testicles with body<unk>  by keeping them in the inguinal sack for several hours a day reduces sperm production below the contraceptive threshold of 1 million/ml. Knowledge of the thermal dependence of spermatogenesis dates back to 1941. However, it was not until 50 years later, in 1991, that the first study reporting the contraceptive effect of<unk>  on men was published: andrologists Roger Mieusset and Jean-Claude Soufir were the first to get results with the artificial cryptorchidism method (testicles held inside the inguinal sack) with the use of suited devices. Thermal insulation of the testis A surgical intervention causes the testicles to be held in the inguinal sack.<unk> ing devices Wearing a device that presses the man's testicles against his body on a daily basis can raise their temperature by 2 °C and thus slow down sperm production. To be effective, the device must be worn daily (approximately 15 hours per day) for at least 3 months, which is equivalent to the sperm's life cycle. This allows the contraceptive threshold of one million per millilitre of sperm to be temporarily reached (compared to an average of 15 to 60 million). Practitioners should do pre- and post-usage testing to check their sperm counts. Various techniques are considered, such as an insulating bag with<unk> ing elements in contact with the scrotum.<unk> ing underwear The<unk> ing briefs are one of the available devices. This method was invented and is prescribed by Doctor Mieusset at the University Hospital of Toulouse. In 2019, a French news channel reported that "only about twenty men were wearing this contraceptive garment in France". It is not sold on the market and a poorly handcrafted design can cause discomfort or irritation. Other "do-it-yourself" models called "jock-strap" or "bra" also exist. Silicone ring Another available device is the silicone ring. Invented and patented by Maxime Labrit, a French nurse, it is available for purchase on the Internet for a few dozen euros. Ultrasounds One method under investigation is ultrasound, which involves the application of high-frequency sound waves to animal tissue, which in turn absorb the sound waves’ energy as<unk> . The possibility for ultrasound's use for<unk>  is<unk>  on the idea that briefly<unk> ing the testes can halt sperm production, leading to temporary infertility for about six months. Additionally, ultrasound could affect cells’ absorption rates of ions, which itself could create an environment unfavorable to spermatogenesis. Its extremely localized effects on animal tissues make ultrasound an attractive candidate for research, but so far studies have only been performed on non-human animals, such as dogs.
Heat-based contraception
Long-acting reversible contraception
Combined hormonal contraception
Male contraceptive
Vas-occlusive contraception
Contraceptive implant
Emergency contraception
Progestogen-only contraception