THE METHOD IN 30 SECONDS
PREAMBLE
Thermal male contraception by testicular lifting (TMC) is an experimental, non-hormonal male contraceptive method that fits easily into everyday life and is already practised by thousands of men. According to initial clinical feedback, it appears to be highly effective and reversible.
PRINCIPLE
Thermal contraception by testicular lifting involves mechanically lifting the testicles above the scrotum. Their temperature then rises, approaching that of the rest of the body: 37°C. At this temperature, sperm production is impaired and fertility decreases. If this is done every day, fertility decreases enough to achieve contraception.
EFFECTIVENESS
Effectiveness is documented by initial clinical trials and user surveys: according to this early work, when thermal contraception is applied following the established medical protocol, its practical effectiveness is comparable to that of the most effective female contraceptives. These results will need to be confirmed in larger-scale studies.
A simple semen analysis makes it possible to check whether it is working at an individual level.
USES
Thermal contraception is intended for any fertile person with post-pubertal testicles who has sex with fertile partners who have ovaries, and who does not want this sex to be able to result in pregnancy.
WHY THIS CONTRACEPTIVE SOLUTION?
AN INEQUITABLE CONTRACEPTIVE LANDSCAPE, INSUFFICIENTLY EFFECTIVE PRACTICES
Today, most of the contraceptive burden falls on women. In practice: side effects, hormonal, invasive and restrictive solutions, imperfect methods… In figures: every year, 2,500 cardiovascular events are caused by the pill.
There is also a degree of ineffectiveness in our contraceptive practices: 1/3 of pregnancies are unplanned, and 2/3 of unplanned pregnancies occur despite the use of contraception. It takes two to conceive, so why not share contraception between two?
A GROWING, UNMET DEMAND
At the other end of the spectrum, the options for men are limited. Today, only two contraceptive methods are available to men: condoms and vasectomy. One is not very spontaneous and not very effective, the other is permanent.
Handmade devices (rings, hand-sewn jockstraps) are used by men to practise thermal contraception by testicular lifting, but they are not recognised by health authorities. Yet in France, more than 10,000 men already use reversible contraception with these devices. The need is urgent, and the knowledge is there.
A WAY TO SHARE THE CONTRACEPTIVE BURDEN
What if widening the choice, by offering a reliable male contraceptive solution that fits into everyday life, could rebalance the contraceptive burden and revolutionise heterosexual relationships? What if contraception were one of the starting points towards a society where intimacy is equitable, fluid and free from gender norms?
HOW DOES THERMAL CONTRACEPTION WORK?
THERMAL CONTRACEPTION IN DETAIL
To produce sperm, the testicles must be kept at a lower temperature than the rest of the body, around 33 to 35°C. By lifting them above the scrotum, their temperature rises towards 37°C. A few degrees that change everything. At this temperature, sperm production is impaired. By warming the testicles in this way every day, it is possible to lower the sperm count enough for the semen to no longer be fertile. No hormones, no surgery, and side effects that appear to be limited. A mechanical action, in principle reversible, whose success can easily be measured with a semen analysis.
Today, this contraceptive practice spreads mainly through associative networks and user communities, such as those listed on the map of associations and collectives or Otoko.
THE IMPLEMENTATION PROTOCOL
For the method to be effective, the protocol must be followed strictly.
- Before starting your contraceptive journey, a consultation with a doctor makes it possible to check that the method is suitable for your body, your health and your contraceptive plans.
- It is then recommended to have a baseline semen analysis, which gives an overview of your spermatogenesis: a starting picture that will serve as a point of comparison later on.
- You can now start wearing your device, 15 hours a day, every day. Breaks are possible, as long as the total is at least 15 hours per 24-hour period. Please note: at this stage, you are not contracepted.
- After 3 months of consistent wear, a semen analysis is used to confirm that contraception is effective. It must show a concentration below 1 million sperm/ml of semen. Until this semen analysis has confirmed contraception, the user must not consider themselves contracepted and must use another method of contraception (condom, pill, IUD, etc.).
- Long-term follow-up by a doctor. Because intimate health is not a matter for guesswork. The device must be worn daily for as long as contraception is wanted.
If you wish to recover your fertility, simply stop wearing the device and it will return within a few months. The return of fertility must be confirmed by a semen analysis. After stopping wear, and until the return of fertility has been confirmed, the user must use another method of contraception (condom, pill, IUD, etc.).
Thermal contraception is not a simple one-off action: it is a method built up over time, with healthcare professionals, regular check-ups and a precise protocol of use.
If you would like some help following the protocol, you can download the OTOKO app, currently in beta, HERE.
Each phase exists to ensure two essential things: the effectiveness of the method and the safety of the user and their partner.
Ask your doctor for advice.
How to use the 37.0 body exploration boxer?
3D
THE DEVELOPMENT OF TMC: A HISTORY
THE WORK OF DR MIEUSSET AND ARDECOM
Before the labs, there were men. In the 1970s, a movement emerged: discussion groups in which men questioned their roles, their desires, their privileges… and their contraceptive responsibility. From these discussions, sometimes painful, often liberating, the Association for Research and Development in Male Contraception (ARDECOM) was born. An association that paved the way. Their conviction? Intimate equity is also built through action.
In the 1980s, Dr Mieusset, an andrologist at Toulouse University Hospital, demonstrated the principle of TMC. Publications began to appear, the data were confirmed, the method worked. This pioneering work, carried out by Dr Mieusset and ARDECOM, led to the development of an undergarment made of elastic bands which, worn daily, can provide contraception for anyone with testicles. This was the birth of the "Toulouse testicle lifter", also known as the "heating briefs" (le "slip chauffant"), even though they do not heat but lift the testicles.
Through successive studies, they demonstrated its reliability and reversibility, set out a precise protocol and defined safe conditions of use. The method has been studied in more than 1,000 participants. Since then, and still today, knowledge in andrology and male fertility has continued to progress, confirming and refining the initial recommendations. To date, the number of users of this method in France is estimated at more than 10,000.
A DEFINED PROTOCOL
Daily wearing time, sperm concentration threshold, time needed to become contracepted, wearing period, time to reversibility: all parameters that clinical trials have made it possible to frame and define with precision and scientific rigour.
THOREME, ANDROSWITCH AND HANDMADE DEVICES
Various devices have appeared in recent years, often handmade. All over France, associations run self-making and awareness workshops: Thomas Boulou (Brittany), GARCON (Toulouse), Zéro Millions (Paris), Treizeticules (Marseille) and many other local collectives. These communities keep this knowledge alive. They explain, sew and weave an essential network.
In 2018, the Andro-switch, a silicone ring made by the company Thoreme, went on sale online and accelerated the spread of the method. In 2021, the ANSM (the French medicines regulator) requested that its sale be halted, as no CE marking had been obtained, but the seed had been planted: users had taken up this method to take control of their fertility.
THE 37 DEGRÉS DEVICE: EVERY DAY, FROM MORNING TO NIGHT
THE ORIGINS OF THE PROJECT
37 DEGRÉS aims to bring together medical innovation, scientific expertise, fashion and easy integration into users' lives.
To find out more about how the project began, visit our About page.
MEDICAL EXPERTISE FOR EVERYDAY LIFE
A scientific advisory board supports every stage of development, from prototype to clinical trial. A soft, adjustable ring structure, a transverse pocket that makes fitting easier, precise support inside the body at 37°C, and ergonomics designed to move with you: every element meets a strictly defined functional requirement.
More than a medical device, the 37 DEGRÉS 37.1 boxer, currently in development, is designed to also be a piece of menswear: a contemporary, understated, elegant and comfortable boxer, made to fit naturally into life and its ups and downs. It will slip on in seconds, adjust in a single movement and be worn all day. The adjustment system will allow the support to be adapted to body shape and activity. Male contraception, finally in the 21st century.
WHAT IS THERMAL CONTRACEPTION?
What does sexual health mean for men?
What is a semen analysis?
OUR DOCTORS ANSWER YOUR QUESTIONS!
