Hormonal, chemical and thermal inhibition of spermatogenesis: contribution of French teams to international data with the aim of developing male contraception in France

Abstract

Since the 1970s, international research on male contraception has been actively pursued. Hormonal and non-hormonal methods (thermal, chemical) have been tested, leading to clinical trials of interest to thousands of men and couples.The results showed that it was possible to develop methods of male contraception that inhibited spermatogenesis with good contraceptive efficacy. However, their side effects (mainly loss of libido), poorly accepted modes of administration, and the high frequency of poor responders prevented their widespread use.Based on earlier initiatives, new avenues were explored and significant progress was achieved, allowing the reasoned use of male contraception. For 40 years, several French teams have played an important role in this research. The aim of this paper is to outline the history and the progress of the experimental and clinical works of these teams who addressed hormonal, chemical and thermal approaches to male contraception. These approaches have led to a better comprehension of spermatogenesis that could be useful in fields other than male contraception: effects of toxic compounds, fertility preservation.

Are men ready to use thermal male contraception? Acceptability in two French populations: New fathers and new providers

“…Many publications have reported “new” methods of male contraception and present hormonal methods versus non-hormonal methods [ 33 – 36 ]. Unfortunately, TMC is only rarely reported [ 7 , 14 , 37 ], and the only non-hormonal methods mentioned are potential “chemical” methods that remain under investigation.…”

“…These disadvantages arise from an imagined expectation. Data regarding TMC comfort are limited because the participants in various TMC trials “were all voluntary demanders of male contraception (thermal and not-hormonal), which may explain the low rate of reported annoyance” [ 14 , 46 ].…”

“…Since the 1970s, international research has actively pursued male contraception, primarily hormonal approaches based on inhibiting gonadotropin secretion by administering exogenous androgen alone [ 10 ] or in combination with progestins [ 11 ] (for review, see [ 12 , 13 ]) and, to a lesser extent, thermal approaches. For both hormonal male contraception (HMC) and thermal male contraception (TMC), a first phase of 2 to 4 months consists of spermatogenesis inhibition to achieve a contraceptive threshold of less than 1 million sperm per mL of semen; once the threshold is obtained, treatments must be continued weekly (HMC, [ 10 ]) or daily (TMC) to maintain the contraceptive level [ 14 ].…”

Barriers in Male Contraception: Literature Review

“…Spermatogenezis, sıcaklık yükselmesinin durmasıyla normale döner. 36 Y Ya ap pa ay y K Kr ri ip pt to or rş şi id di iz zm m ( (S Su us sp pe en ns so or ri ie es s) ): : Hayvanlarda kriptorşid (inmemiş) testislerin infertilite nedeni olduğu yüzyıllardır bilinmektedir. Testis sıcaklığında küçük bir artışın bile sperm üretimi (spermatogenez) üzerinde büyük bir olumsuz etkisi vardır.…”

Experimental mild increase in testicular temperature has drastic, but reversible, effect on sperm aneuploidy in men: A pilot study

“…It has been suggested that a modification of testicular temperature could be used in two ways: increasing testes temperature to inhibit spermatogenesis or decreasing it to improve spermatogenesis in infertile men who have abnormally elevated testes temperatures. Experimental studies [29][30][31] and reviews [32][33][34] have reported that a mild testis temperature increase could be used as a male contraceptive approach. On the other hand, reducing the testicular temperature using application of an ice bag for 30 min per day for 14 days improves 7 spermatogenesis outcome [35].…”