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Lee MS, Bunin DI, Furimsky AM, Nguyen D, Parman T, Kim K, Rausch L, Lin MT, Gupta P, Brown JE, Kroopnick JM, Blithe DL. Novel progestogenic androgens for male contraception: design, synthesis, and activity of C7 α-substituted testosterone†. Biol Reprod 2023; 109:851-863. [PMID: 37669128 PMCID: PMC10724455 DOI: 10.1093/biolre/ioad111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 08/08/2023] [Accepted: 08/30/2023] [Indexed: 09/07/2023] Open
Abstract
Male contraceptive development has included use of testosterone (T) with or without a progestin or the use of a single molecule such as progestogenic androgens (PA) for suppression of testicular T production. Expanding upon the vast amount of data accumulated from nortestosterone (NT), NT analogs, and their prodrugs, a new series of PA, the C7 methyl, and ethyl α-substituted T analogs 7α-Methyltestosterone (7α-MT) and 7α-Ethyltestosterone (7α-ET), respectively, were hypothesized and designed to have superior androgenic and progestogenic activities when compared with parent T. Results from androgen receptor and progesterone receptor competitive binding and transcriptional activation assays showed favorable activities for these T analogs. Additionally, 7α-MT and 7α-ET were shown to be active substrates for aromatase in vitro, mitigating a potential negative impact on bone mineral density with long-term use. In conjunction with this observation, the diminished metabolism of these T analogs by 5α-reductase may reduce potential concerns for prostatic growth. In the Hershberger in vivo rat bioassay, 7α-MT and 7α-ET showed superior androgenic and anabolic activities as compared with T. These C7 α-substituted T analogs also showed clear progestogenic activity in the McPhail bioassay which evaluated endometrial glandular arborization in a rabbit model. The discovery of aromatizable molecules with reduced metabolism by 5α-reductase that have androgenic, anabolic, and progestogenic properties indicates that the core and/or prodrugs of 7α-MT and 7α-ET are promising molecules for further development as male contraceptive PAs.
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Affiliation(s)
- Min S Lee
- Contraceptive Development Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institute of Health, Bethesda, MD, USA
| | - Deborah I Bunin
- Biosciences Division, SRI International, Menlo Park, CA, USA
| | - Anna M Furimsky
- Biosciences Division, SRI International, Menlo Park, CA, USA
| | - Donna Nguyen
- Biosciences Division, SRI International, Menlo Park, CA, USA
| | | | - Kyuri Kim
- Jazz Pharmaceuticals, Palo Alto, CA, USA
| | - Linda Rausch
- Biosciences Division, SRI International, Menlo Park, CA, USA
| | | | | | - Jill E Brown
- Department of Gynecologic Surgery & Obstetrics, Uniformed Services University, Bethesda, MD, USA
| | - Jeffrey M Kroopnick
- Contraceptive Development Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institute of Health, Bethesda, MD, USA
| | - Diana L Blithe
- Contraceptive Development Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institute of Health, Bethesda, MD, USA
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Gómez-Torres P, Lucha-López AC, Martínez-Pérez GZ, Sheridan T, Vera Cruz G. Acceptability and Determinants of using Male Hormonal Contraceptives: A Systematic Review from a Gender Perspective. PSYCHOLOGY & SEXUALITY 2023. [DOI: 10.1080/19419899.2023.2191606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
Affiliation(s)
- Piedad Gómez-Torres
- Department of Physiatrics and Nursing, University of Zaragoza, Zaragoza, Spain
- Research Group Sector III Heathcare (GIIS081), Institute of Research of Aragón, Zaragoza, Spain
| | - Ana C. Lucha-López
- Department of Physiatrics and Nursing, University of Zaragoza, Zaragoza, Spain
- Research Group Sector III Heathcare (GIIS081), Institute of Research of Aragón, Zaragoza, Spain
- Unidad de Investigación en Fisioterapia (UIF), University of Zaragoza, Zaragoza, Spain
| | | | - Taylor Sheridan
- Barcelona Institute for Global Health (ISGlobal), University of Barcelona, Barcelona, Spain
| | - Germano Vera Cruz
- Department of Psychology, University of Picardie Jules Verne, Amiens, France
- Centre de Recherche en Psychologie: Cognition, Psychisme et Organisations UR 7273 CRP-CPO, University of Picardie Jules Verne, Amiens, France
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Abbe C, Roxby AC. Assessing safety in hormonal male contraception: a critical appraisal of adverse events reported in a male contraceptive trial. BMJ SEXUAL & REPRODUCTIVE HEALTH 2020; 46:139-146. [PMID: 31754066 PMCID: PMC8029306 DOI: 10.1136/bmjsrh-2018-200206] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Revised: 10/29/2019] [Accepted: 10/30/2019] [Indexed: 06/10/2023]
Abstract
INTRODUCTION There is unmet need for male contraceptive options, but a recent injectable combination male contraceptive trial was terminated early due to adverse events (AEs). METHODS We examined the frequency of reported AEs by male research participants compared with AEs reported in prescribing information of approved female hormonal contraceptive methods. Published data from trials of the top five most-used female hormonal contraceptives, supplemented by contemporary contraceptive research, were compared with the frequency of AEs reported in a male injectable hormonal contraceptive trial. RESULTS We observed similar frequencies of AEs reported by users of male contraceptives compared with those reported by female users. Among quantitatively comparable AEs, compared with men, women reported experiencing higher frequencies of headaches, pelvic pain, and weight gain and similar frequencies of decreased libido. Compared with women, men reported experiencing higher frequencies of acne and mood changes. Men discontinued participation due to AEs at a lower frequency than women. CONCLUSIONS Female hormonal methods generally have similar frequencies of AEs to those reported in a recent male hormonal contraceptive trial, and male users had lower rates of discontinuation due to AEs. There were fewer serious AEs of the male contraceptive than reported in contemporary female trials which resulted in FDA licensure. This suggests there may be implicit bias in the scientific community regarding the level of acceptable risk for users of male contraceptive methods.
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Affiliation(s)
- Carmen Abbe
- Department of Medicine, University of Washington, Seattle, Washington, USA
- Scripps College, Claremont, California, United States
| | - Alison C Roxby
- Department of Medicine, University of Washington, Seattle, Washington, USA
- Department of Global Health, University of Washington, Seattle, United States
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Amory JK. Development of Novel Male Contraceptives. Clin Transl Sci 2020; 13:228-237. [PMID: 31618525 PMCID: PMC7070810 DOI: 10.1111/cts.12708] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 09/03/2019] [Indexed: 12/16/2022] Open
Abstract
Unintended pregnancy is surprisingly common, accounting for 40-50% of pregnancies worldwide. Contraception is the most effective means of preventing unintended pregnancy. Seventy percent of all contraceptives are used by women; however, some women are unable to use contraceptives due to health conditions or side effects. Many men wish to take a more active role family planning, but currently have only two effective male contraceptive options, condoms and vasectomy. Therefore, work to develop novel male contraceptives analogous to popular female methods, such as daily pills or long-acting shots and implants, is underway. This paper will briefly discuss the pros and cons of condoms and vasectomies, and then review the research into novel methods of male contraception.
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Affiliation(s)
- John K. Amory
- Department of MedicineCenter for Research in Reproduction and ContraceptionUniversity of WashingtonSeattleWashingtonUSA
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Frankiewicz M, Połom W, Matuszewski M. Can the evolution of male contraception lead to a revolution? Review of the current state of knowledge. Cent European J Urol 2018; 71:108-113. [PMID: 29732216 PMCID: PMC5926633 DOI: 10.5173/ceju.2017.1450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 12/17/2017] [Accepted: 12/22/2017] [Indexed: 11/22/2022] Open
Abstract
Introduction Great advances in medical research concerning methods of contraception have been achieved in recent years, however, more than 25% of couples worldwide still rely on condoms - a method with poor efficacy. Even though there is a spectrum of 11 different contraceptive methods for women, there are only 4 commonly used by men (condoms, periodic abstinence, withdrawal and vasectomy). In this review, advances and present, state-of-the-art, both hormonal and non-hormonal male contraceptive methods will be presented and evaluated. Potential novel targets that warrant greater research will be highlighted. Material and methods A comprehensive literature search without a time limit was performed using the Medline database on May 2017. The terms 'male contraception' in conjunction with 'reversible inhibition of sperm under guidance' (RISUG), 'hormonal', 'non-hormonal', 'vasectomy' or 'testosterone' were used. The articles were limited to those published in English, Polish or French. Results There are various contraceptives currently available to regulate male fertility. Vasectomy is still the most effective permanent form of male contraceptive with a failure rate lower than 1%. Reversible, non hormonal methods of male contraception, like reversible inhibition of sperm under guidance, are very promising and close to being introduced into the market. In regards to hormonal contraception research, the use of testosterone injections has been widely studied yet they often harbor undesirable side effects and require further development. Conclusions Despite continuous efforts worldwide, it seems that another several years of research is needed to provide safe, effective and affordable male contraceptives which will allow both men and women to participate fully in family planning.
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Affiliation(s)
| | - Wojciech Połom
- Department of Urology Medical University of Gdańsk, Gdańsk, Poland
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Abstract
Although female contraceptives are very effective at preventing unintended pregnancy, some women can not use them because of health conditions or side-effects, leaving some couples without effective contraceptive options. In addition, many men wish to take active responsibility for family planning. Thus, there is a great need for male contraceptives to prevent unintended pregnancies, of which 80-90 million occur annually. At present, effective male contraceptive options are condoms and vasectomy, which are not ideal for all men. Therefore, efforts are under way to develop novel male contraceptives. This paper briefly reviews the advantages and disadvantages of condoms and vasectomies and then discusses the research directed toward development of novel methods of male contraception.
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Affiliation(s)
- John K Amory
- Center for Research in Reproduction and Contraception, Department of Medicine, University of Washington, Seattle, Washington.
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Abstract
World population continues to grow at an unprecedented rate, doubling in a mere 50years to surpass the 7-billion milestone in 2011. This steep population growth exerts enormous pressure on the global environment. Despite the availability of numerous contraceptive choices for women, approximately half of all pregnancies are unintended and at least half of those are unwanted. Such statistics suggest that there is still a gap in contraceptive options for couples, particularly effective reversible contraceptives for men, who have few contraceptive choices. Male hormonal contraception has been an active area of research for almost 50years. The fundamental concept involves the use of exogenous hormones to suppress endogenous production of gonadotropins, testosterone, and downstream spermatogenesis. Testosterone-alone regimens are effective in many men but high dosing requirements and sub-optimal gonadotropin suppression in 10-30% of men limit their use. A number of novel combinations of testosterone and progestins have been shown to be more efficacious but still require further refinement in delivery systems and a clearer understanding of the potential short- and long-term side effects. Recently, synthetic androgens with both androgenic and progestogenic activity have been developed. These agents have the potential to be single-agent male hormonal contraceptives. Early studies of these compounds are encouraging and there is reason for optimism that these may provide safe, reversible, and reliable contraception for men in the near future.
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Affiliation(s)
- Jing H Chao
- Division of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, WA, USA
| | - Stephanie T Page
- Division of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, WA, USA.
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Abstract
Nearly half of all pregnancies worldwide are unplanned, despite numerous contraceptive options available. No new contraceptive method has been developed for men since the invention of condom. Nevertheless, more than 25% of contraception worldwide relies on male methods. Therefore, novel effective methods of male contraception are of interest. Herein we review the physiologic basis for both male hormonal and nonhormonal methods of contraception. We review the history of male hormonal contraception development, current hormonal agents in development, as well as the potential risks and benefits of male hormonal contraception options for men. Nonhormonal methods reviewed will include both pharmacological and mechanical approaches in development, with specific focus on methods which inhibit the testicular retinoic acid synthesis and action. Multiple hormonal and nonhormonal methods of male contraception are in the drug development pathway, with the hope that a reversible, reliable, safe method of male contraception will be available to couples in the not too distant future.
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Affiliation(s)
- Mara Y Roth
- Department of Medicine, Center for Research in Reproduction and Contraception, University of Washington, Seattle, Washington
| | - John K Amory
- Department of Medicine, Center for Research in Reproduction and Contraception, University of Washington, Seattle, Washington
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Roth MY, Page ST, Bremner WJ. Male hormonal contraception: looking back and moving forward. Andrology 2015; 4:4-12. [PMID: 26453296 DOI: 10.1111/andr.12110] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 08/11/2015] [Accepted: 08/26/2015] [Indexed: 11/26/2022]
Abstract
Despite numerous contraceptive options available to women, approximately half of all pregnancies in the United States and worldwide are unplanned. Women and men support the development of reversible male contraception strategies, but none have been brought to market. Herein we review the physiologic basis for male hormonal contraception, the history of male hormonal contraception development, currents agents in development as well as the potential risks and benefits of male hormonal contraception for men.
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Affiliation(s)
- M Y Roth
- Department of Medicine and Center for Research in Reproduction and Contraception, University of Washington, Seattle, WA, USA
| | - S T Page
- Department of Medicine and Center for Research in Reproduction and Contraception, University of Washington, Seattle, WA, USA
| | - W J Bremner
- Department of Medicine and Center for Research in Reproduction and Contraception, University of Washington, Seattle, WA, USA
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Papillon-Smith J, Baker SE, Agbo C, Dahan MH. Pregnancy rates with intrauterine insemination: comparing 1999 and 2010 World Health Organization semen analysis norms. Reprod Biomed Online 2014; 30:392-400. [PMID: 25682304 DOI: 10.1016/j.rbmo.2014.12.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Revised: 12/07/2014] [Accepted: 12/09/2014] [Indexed: 10/24/2022]
Abstract
Over the past 30 years, The World Health Organization has serially measured norms for human sperm. In this study, 1999 and 2010 semen analysis norms as predictors of pregnancy were compared during intrauterine insemination (IUI). A retrospective cohort study was conducted using data collected from the Stanford Fertility Center, between 2005 and 2007, with 981 couples undergoing 2231 IUI cycles. Collected semen was categorized according to total motile sperm counts (TMSC): 'normal (N.) 1999 TMSC', 'abnormal (AbN.) 1999/N. 2010 TMSC', or 'AbN. 2010 TMSC'. Sample comparison was also based on individual semen parameters: 'N. 1999 WHO', 'AbN. 1999/N. 2010 WHO', or 'AbN. 2010 WHO'. Pregnancy (defined by beta-HCG concentration) rates were calculated. Data were compared using correlation coefficients, t-tests and chi-squared tests, with and without adjusting for confounders. Pregnancy rate comparison based on TMSC ('N. 1999 TMSC', 'AbN. 1999/N. 2010 TMSC' and 'AbN. 2010 TMSC') showed a negative correlation (r = -0.41, P = 0.05). Pregnancy rate did not differ when comparisons were based on the presence of abnormal parameters, even when controlling for confounders. Therefore, TMSC based on the 1999 parameters shows best correlation with pregnancy rate for IUI; updating these norms in 2010 has little clinical implication in infertile populations.
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Affiliation(s)
- J Papillon-Smith
- Department of Obstetrics and Gynecology, McGill University, 687 Pine Ave West, Montreal, QC, Canada H3A 1A1.
| | - S E Baker
- High School Student Summer Research Rotation, Stanford Medical School, 291 Campus Drive, Li Ka Shing Building, 3rd floor, Stanford, CA, USA
| | - C Agbo
- Stanford University School of Medicine, 291 Campus Drive, Li Ka Shing Building, 3rd floor, Stanford, CA, USA
| | - M H Dahan
- Department of Obstetrics and Gynecology, McGill University, 687 Pine Ave West, Montreal, QC, Canada H3A 1A1
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Male contraception. Best Pract Res Clin Obstet Gynaecol 2014; 28:845-57. [PMID: 24947599 DOI: 10.1016/j.bpobgyn.2014.05.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Revised: 03/13/2014] [Accepted: 05/26/2014] [Indexed: 12/21/2022]
Abstract
Clear evidence shows that many men and women would welcome new male methods of contraception, but none have become available. The hormonal approach is based on suppression of gonadotropins and thus of testicular function and spermatogenesis, and has been investigated for several decades. This approach can achieve sufficient suppression of spermatogenesis for effective contraception in most men, but not all; the basis for these men responding insufficiently is unclear. Alternatively, the non-hormonal approach is based on identifying specific processes in sperm development, maturation and function. A range of targets has been identified in animal models, and targeted effectively. This approach, however, remains in the pre-clinical domain at present. There are, therefore, grounds for considering that safe, effective and reversible methods of contraception for men can be developed.
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Mostaghel EA, Lin DW, Amory JK, Wright JL, Marck BT, Nelson PS, Matsumoto AM, Bremner WJ, Page ST. Impact of male hormonal contraception on prostate androgens and androgen action in healthy men: a randomized, controlled trial. J Clin Endocrinol Metab 2012; 97:2809-17. [PMID: 22659250 PMCID: PMC3410271 DOI: 10.1210/jc.2012-1536] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Male hormonal contraception (MHC) combines hypothalamic-pituitary-gonadal axis blockade with exogenous androgen delivery to maintain extragonadal androgen end-organ effects. Concern exists that MHC may adversely impact prostate health. OBJECTIVE The objective of the study was to determine the molecular impact of MHC on intraprostatic androgen concentrations and androgen action. DESIGN This was a single-blind, randomized, placebo-controlled study. SETTING The study was conducted at an academic medical center. PARTICIPANTS 32 healthy men aged 25-55 yr participated in the study. INTERVENTION Interventions included placebo, daily transdermal testosterone (T) (T-gel), T-gel + depomedroxyprogesterone acetate (T+DMPA), or T-gel + dutasteride daily (T+D) for 12 wk, and prostate biopsy during treatment wk 10. MAIN OUTCOME MEASURES Serum and prostate androgen concentrations and prostate epithelial-cell gene expression were measured. RESULTS Thirty men completed the study. Serum T levels were significantly increased in T-gel and T+D groups compared with baseline (P < 0.05) but were decreased with the addition of DMPA. Intraprostatic androgens were no different from placebo with T-gel treatment. Addition of DMPA to T resulted in 40% lower intraprostatic dihydrotestosterone (DHT) concentration (P = 0.0273 vs. placebo), whereas combining dutasteride with T resulted in a 90% decrease in intraprostatic DHT (P = 0.0012), 11-fold increased intraprostatic T (P = 0.0011), and 7-fold increased intraprostatic androstenedione (P = 0.0011). Significant differences in global or androgen-regulated prostate epithelial-cell gene expression were not observed. Androgen-regulated gene expression correlated with epithelial-cell androgen receptor and prostatic DHT in placebo, T-gel, and T+DMPA arms and with T and androstenedione levels in the T+D arm. CONCLUSIONS MHC regimens do not markedly alter gene expression in benign prostate epithelium, suggesting they may not alter risk of prostate disease. Longer-term studies examining the impact of MHC on prostate health are needed.
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Affiliation(s)
- Elahe A Mostaghel
- Division of Human Biology and Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA
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Abstract
BACKGROUND Male hormonal contraception has been an elusive goal. Administration of sex steroids to men can shut off sperm production through effects on the pituitary and hypothalamus. However, this approach also decreases production of testosterone, so 'add-back' therapy is needed. OBJECTIVES To summarize all randomized controlled trials (RCTs) of male hormonal contraception. SEARCH METHODS In January and February 2012, we searched the computerized databases CENTRAL, MEDLINE, POPLINE, and LILACS. We also searched for recent trials in ClinicalTrials.gov and ICTRP. Previous searches included EMBASE. We wrote to authors of identified trials to seek additional unpublished or published trials. SELECTION CRITERIA We included all RCTs that compared a steroid hormone with another contraceptive. We excluded non-steroidal male contraceptives, such as gossypol. We included both placebo and active-regimen control groups. DATA COLLECTION AND ANALYSIS The primary outcome measure was the absence of spermatozoa on semen examination, often called azoospermia. Data were insufficient to examine pregnancy rates and side effects. MAIN RESULTS We found 33 trials that met our inclusion criteria. The proportion of men who reportedly achieved azoospermia or had no detectable sperm varied widely. A few important differences emerged. 1) Levonorgestrel implants (160 μg daily) combined with injectable testosterone enanthate (TE) were more effective than levonorgestrel 125 µg daily combined with testosterone patches. 2) Levonorgestrel 500 μg daily improved the effectiveness of TE 100 mg injected weekly. 3) Levonorgestrel 250 μg daily improved the effectiveness of testosterone undecanoate (TU) 1000 mg injection plus TU 500 mg injected at 6 and 12 weeks. 4) Desogestrel 150 μg was less effective than desogestrel 300 μg (with testosterone pellets). 5) TU 500 mg was less likely to produce azoospermia than TU 1000 mg (with levonorgestrel implants). 6) Norethisterone enanthate 200 mg with TU 1000 mg led to more azoospermia when given every 8 weeks versus 12 weeks. 7) Four implants of 7-alpha-methyl-19-nortestosterone (MENT) were more effective than two MENT implants. We did not conduct any meta-analysis due to intervention differences.Several trials showed promising efficacy in percentages with azoospermia. Three examined desogestrel and testosterone preparations or etonogestrel and testosterone, and two examined levonorgestrel and testosterone. AUTHORS' CONCLUSIONS No male hormonal contraceptive is ready for clinical use. Most trials were small exploratory studies. Their power to detect important differences was limited and their results imprecise. In addition, assessment of azoospermia can vary by sensitivity of the method used. Future trials need more attention to the methodological requirements for RCTs. More trials with adequate power would also be helpful.
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Affiliation(s)
- David A Grimes
- Obstetrics and Gynecology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA.
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Zitzmann M. Hormonelle Kontrazeption beim Mann. GYNAKOLOGISCHE ENDOKRINOLOGIE 2012. [DOI: 10.1007/s10304-011-0447-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Walker S. Attitudes to a male contraceptive pill in a group of contraceptive users in the UK. JOURNAL OF MENS HEALTH 2011. [DOI: 10.1016/j.jomh.2011.04.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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[Hormonal contraception for men: still a current issue]. Urologe A 2010; 49:16-9. [PMID: 20057989 DOI: 10.1007/s00120-009-2193-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The current status of hormonal contraception in men involves the principle of suppression of gonadotropins, LH, and FSH. This must be achieved as completely as possible to facilitate cessation of spermatogenesis and, thus, reach azoospermia. Simultaneously testosterone has to be replaced. Exogenous testosterone administration achieves the goal of gonadotropin suppression, but needs in addition the supplementation of a gestagen to fully suppress secretion of LH and FSH. Suppression of gonadotropins by steroids requires constant serum concentrations of sex steroids; hence, attempts using daily oral or transdermal preparations were, so far, unsuccessful. Thus, the immediate prospect for male contraception is not a"pill" itself but a regimen of combined injectable steroids, which are in advanced clinical testing.
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Huhtaniemi I. A Hormonal Contraceptive for Men: How Close are We? PROGRESS IN BRAIN RESEARCH 2010; 181:273-88. [DOI: 10.1016/s0079-6123(08)81015-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Cooper TG, Noonan E, von Eckardstein S, Auger J, Baker HG, Behre HM, Haugen TB, Kruger T, Wang C, Mbizvo MT, Vogelsong KM. World Health Organization reference values for human semen characteristics*‡. Hum Reprod Update 2009; 16:231-45. [DOI: 10.1093/humupd/dmp048] [Citation(s) in RCA: 1747] [Impact Index Per Article: 116.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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Misro MM, Chaki SP, Kaushik MC, Nandan D. Trials for development of once-a-month injectable, hormonal male contraceptive using dienogest plus testosterone undecanoate: dose standardization, efficacy and reversibility studies in rats. Contraception 2009; 79:488-97. [PMID: 19442786 DOI: 10.1016/j.contraception.2009.01.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2008] [Revised: 11/27/2008] [Accepted: 01/06/2009] [Indexed: 11/19/2022]
Abstract
BACKGROUND The study was conducted to test the potential of using dienogest (DNG) plus testosterone undecanoate (TU) in rats for development of a once-a-month injectable male hormonal contraceptive. STUDY DESIGN Dose selection studies were initiated with administration of DNG in three different doses of 20, 30 and 40 mg/kg body weight (bw) per week plus TU 25 mg/kg bw once in every 6 weeks. Status of spermatogenesis and sperm count in epididymis was evaluated. The frequency of DNG intervention was later extended to every 2- and 4-week intervals. Mating studies, toxicity and reversibility of spermatogenesis following stoppage of treatment were carried out with DNG 40 mg/kg bw at 4-week intervals. RESULTS Complete arrest of spermatogenesis was observed after 60 days of treatment at all doses of DNG (20, 30 and 40 mg/kg bw per week)+TU. However, weights of testis and accessory sex organs (epididymis, prostate and seminal vesicle) declined significantly 60 days post treatment compared to vehicle-treated controls. Epididymis in the treated animals was completely devoid of sperm. When the frequency of DNG injection (20 mg/kg bw) was extended to once every 15 days, a few immotile and decapitated sperm were observed in the epididymis. With TU treatment unchanged, animals receiving DNG (40 mg/kg bw) once either every 2- or 4-week intervals demonstrated good and uniform arrest of spermatogenesis. DNG 40 mg/kg per 4 weeks+TU also demonstrated a significant rise in germ cell apoptosis in the seminiferous epithelium. There was no significant increase in the serum high-density lipoprotein and low-density lipoprotein levels at the end of 120 days of treatment. Following withdrawal of treatment after 60 or 120 days, qualitative restoration of spermatogenesis was rapid in the former compared to the latter. CONCLUSION Dienogest plus TU has the potential for development as a monthly injectable showing reversible hormonal male contraception with good efficacy.
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Affiliation(s)
- Man M Misro
- Department of Reproductive Biomedicine, National Institute of Health and Family Welfare, New Delhi, India.
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Mommers E, Kersemaekers WM, Elliesen J, Kepers M, Apter D, Behre HM, Beynon J, Bouloux PM, Costantino A, Gerbershagen HP, Grønlund L, Heger-Mahn D, Huhtaniemi I, Koldewijn EL, Lange C, Lindenberg S, Meriggiola MC, Meuleman E, Mulders PFA, Nieschlag E, Perheentupa A, Solomon A, Väisälä L, Wu FC, Zitzmann M. Male hormonal contraception: a double-blind, placebo-controlled study. J Clin Endocrinol Metab 2008; 93:2572-80. [PMID: 18413423 DOI: 10.1210/jc.2008-0265] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
BACKGROUND This study was performed to assess spermatogenesis suppression and safety of a new combination of an etonogestrel (ENG) implant combined with testosterone undecanoate (TU) injections for male contraception. This is the first large placebo-controlled study for male hormonal contraception. DESIGN AND STUDY SUBJECTS In this double-blind, multicenter study, we randomly assigned 354 healthy men to receive either a low- or high-release ENG implant sc combined with im TU injections (750 mg every 10 or 12 wk or 1000 mg every 12 wk) or placebo implant and injections. Treatment duration was 42 or 44 wk and posttreatment follow-up at least 24 wk. RESULTS Overall, spermatogenesis was suppressed to 1 million/ml or less at wk 16 in 89% of men, with approximately 94% in two high-release ENG groups. Suppression was maintained up to the end of the treatment period in 91% of men. For all men who completed the treatment period, 3% never achieved 1 million/ml or less. Median recovery time to a sperm concentration above 20 million/ml was 15 wk (mean 17 wk, 95% confidence interval 16-18 wk). Treatment was well tolerated. As compared with the placebo group, more men in the active treatment groups reported adverse events such as weight gain, mood changes, acne, sweating, or libido change. For both spermatogenesis suppression and safety, differences were small between the active treatment groups. CONCLUSIONS The combination of an ENG implant with TU injections is a well-tolerated male hormonal method, providing effective and reversible suppression of spermatogenesis. Although the results are good, there is still room for improvement, possibly by adjusting the dose regimen or changing the mode of application.
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Affiliation(s)
- Ellen Mommers
- Global Clinical Development Department, Organon, part of Schering-Plough, Oss, The Netherlands.
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Abstract
Despite significant advances in contraceptive options for women over the last 50 yr, world population continues to grow rapidly. Scientists and activists alike point to the devastating environmental impacts that population pressures have caused, including global warming from the developed world and hunger and disease in less developed areas. Moreover, almost half of all pregnancies are still unwanted or unplanned. Clearly, there is a need for expanded, reversible, contraceptive options. Multicultural surveys demonstrate the willingness of men to participate in contraception and their female partners to trust them to do so. Notwithstanding their paucity of options, male methods including vasectomy and condoms account for almost one third of contraceptive use in the United States and other countries. Recent international clinical research efforts have demonstrated high efficacy rates (90-95%) for hormonally based male contraceptives. Current barriers to expanded use include limited delivery methods and perceived regulatory obstacles, which stymie introduction to the marketplace. However, advances in oral and injectable androgen delivery are cause for optimism that these hurdles may be overcome. Nonhormonal methods, such as compounds that target sperm motility, are attractive in their theoretical promise of specificity for the reproductive tract. Gene and protein array technologies continue to identify potential targets for this approach. Such nonhormonal agents will likely reach clinical trials in the near future. Great strides have been made in understanding male reproductive physiology; the combined efforts of scientists, clinicians, industry and governmental funding agencies could make an effective, reversible, male contraceptive an option for family planning over the next decade.
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Affiliation(s)
- Stephanie T Page
- Center for Research in Reproduction and Contraception, Department of Medicine, University of Washington School of Medicine, Seattle, Washington 98195, USA.
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23
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Abstract
PURPOSE OF REVIEW Testosterone functions as a contraceptive by suppressing the secretion of luteinizing hormone and follicle-stimulating hormone from the pituitary. Low concentrations of these hormones deprive the testes of the signals required for spermatogenesis and results in markedly decreased sperm concentrations and effective contraception in a majority of men. Male hormonal contraception is well tolerated and acceptable to most men. Unfortunately, testosterone-alone regimens fail to completely suppress spermatogenesis in all men, meaning that in some the potential for fertility remains. RECENT FINDINGS Because of this, novel combinations of testosterone and progestins, which synergistically suppress gonadotropins, have been studied. Two recently published testosterone/progestin trials are particularly noteworthy. In the first, a long-acting injectable testosterone ester, testosterone decanoate, was combined with etonogestrel implants and resulted in 80-90% of subjects achieving a fewer than 1 million sperm per milliliter. In the second, a daily testosterone gel was combined with 3-monthly injections of depot medroxyprogesterone acetate producing similar results. SUMMARY Testosterone-based hormone combinations are able to reversibly suppress human spermatogenesis; however, a uniformly effective regimen has remained elusive. Nevertheless, improvements, such as the use of injectable testosterone undecanoate, may lead to a safe, reversible and effective male contraceptive.
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Affiliation(s)
- John K Amory
- Center for Research in Reproduction and Contraception, Department of Medicine, University of Washington, Seattle, Washington 98195, USA.
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Within subject variance and estimating degrees of confidence that 0 sperm is the true value? Fertil Steril 2008; 89:1277. [DOI: 10.1016/j.fertnstert.2008.02.098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Liu PY, Swerdloff RS, Anawalt BD, Anderson RA, Bremner WJ, Elliesen J, Gu YQ, Kersemaekers WM, McLachlan RI, Meriggiola MC, Nieschlag E, Sitruk-Ware R, Vogelsong K, Wang XH, Wu FCW, Zitzmann M, Handelsman DJ, Wang C. Determinants of the rate and extent of spermatogenic suppression during hormonal male contraception: an integrated analysis. J Clin Endocrinol Metab 2008; 93:1774-83. [PMID: 18303073 PMCID: PMC5393365 DOI: 10.1210/jc.2007-2768] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2007] [Accepted: 02/20/2008] [Indexed: 11/19/2022]
Abstract
CONTEXT Male hormonal contraceptive methods require effective suppression of sperm output. OBJECTIVE The objective of the study was to define the covariables that influence the rate and extent of suppression of spermatogenesis to a level shown in previous World Health Organization-sponsored studies to be sufficient for contraceptive purposes (< or =1 million/ml). DESIGN This was an integrated analysis of all published male hormonal contraceptive studies of at least 3 months' treatment duration. SETTING Deidentified individual subject data were provided by investigators of 30 studies published between 1990 and 2006. PARTICIPANTS A total of 1756 healthy men (by physical, blood, and semen exam) aged 18-51 yr of predominantly Caucasian (two thirds) or Asian (one third) descent were studied. This represents about 85% of all the published data. INTERVENTION(S) Men were treated with different preparations of testosterone, with or without various progestins. MAIN OUTCOME MEASURE Semen analysis was the main measure. RESULTS Progestin coadministration increased both the rate and extent of suppression. Caucasian men suppressed sperm output faster initially but ultimately to a less complete extent than did non-Caucasians. Younger age and lower initial blood testosterone or sperm concentration were also associated with faster suppression, but the independent effect sizes for age and baseline testicular function were relatively small. CONCLUSION Male hormonal contraceptives can be practically applied to a wide range of men but require coadministration of an androgen with a second agent (i.e. progestin) for earlier and more complete suppression of sperm output. Whereas considerable progress has been made toward defining clinically effective combinations, further optimization of androgen-progestin treatment regimens is still required.
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Affiliation(s)
- Peter Y Liu
- Department of Andrology, ANZAC Research Institute, University of Sydney and Concord Hospital, Concord, New South Wales 2139, Australia.
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Amory JK, Kalhorn TF, Page ST. Pharmacokinetics and pharmacodynamics of oral testosterone enanthate plus dutasteride for 4 weeks in normal men: implications for male hormonal contraception. ACTA ACUST UNITED AC 2007; 29:260-71. [PMID: 18046048 DOI: 10.2164/jandrol.107.004226] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Oral administration of testosterone enanthate (TE) and dutasteride increases serum testosterone and might be useful for male hormonal contraception. To ascertain the contraceptive potential of oral TE and dutasteride by determining the degree of gonadotropin suppression mediated by 4 weeks of oral TE plus dutasteride, 20 healthy young men were randomly assigned to 4 weeks of either 400 mg oral TE twice daily or 800 mg oral TE once daily in a double-blinded, controlled fashion at a single site. All men received 0.5 mg dutasteride daily. Blood for measurement of serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, dihydrotesterone (DHT), and estradiol was obtained prior to treatment, weekly during treatment, and 1, 2, 4, 8, 12, 13, 14, 16, 20, and 24 hours after the morning dose on the last day of treatment. FSH was significantly suppressed throughout treatment with 800 mg TE once daily and after 4 weeks of treatment with 400 mg TE twice daily. LH was significantly suppressed after 2 weeks of treatment with 800 mg TE, but not with 400 mg TE. Serum DHT was suppressed and serum estradiol increased during treatment in both groups. High-density lipoprotein cholesterol was suppresed during treatment, but liver function tests, hematocrit, creatinine, mood, and sexual function were unaffected. The administration of 800 mg oral TE daily combined with dutasteride for 28 days significantly suppresses gonadotropins without untoward side effects and might have utility as part of a male hormonal contraceptive regimen.
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Affiliation(s)
- John K Amory
- Center for Research in Reproduction and Contraception, University of Washington, Box 356429, 1959 NE Pacific St, Seattle, WA 98195, USA.
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27
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Abstract
BACKGROUND Male hormonal contraception has been an elusive goal. Administration of sex steroids to men can shut off sperm production through effects on the pituitary and hypothalamus. However, this approach also decreases production of testosterone, so 'add-back' therapy is needed. OBJECTIVES To summarize all randomized controlled trials of male hormonal contraception. SEARCH STRATEGY We searched the computerized databases CENTRAL, MEDLINE, EMBASE, POPLINE, and LILACS (each from inception to March 2006) for randomized controlled trials of hormonal contraception in men. We wrote to authors of identified trials to seek unpublished or published trials that we might have missed. SELECTION CRITERIA We included all randomized controlled trials in any language that compared a steroid hormone with another contraceptive. We excluded non-steroidal male contraceptives, such as gossypol. We included both placebo and active-regimen control groups. All trials identified included only healthy men with normal semen analyses. DATA COLLECTION AND ANALYSIS Azoospermia (absence of spermatozoa on semen examination) was the primary outcome measure. Data were insufficient to examine pregnancy rates and side effects. MAIN RESULTS We found 30 trials that met our inclusion criteria. The proportion of men who achieved azoospermia varied widely in reports to date. A few important differences emerged from these trials: levonorgestrel implants combined with injectable testosterone enanthate (TE) were more effective than levonorgestrel 125 microg daily combined with testosterone patches; levonorgestrel 500 mug daily improved the effectiveness of TE 100 mg injected weekly; desogestrel 150 mug was less effective than desogestrel 300 mug (with testosterone pellets); testosterone undecanoate (TU) 500 mg was less likely to produce azoospermia than TU 1000 mg (with levonorgestrel implants); norethisterone enanthate 200 mg with TU 1000 mg led to more azoospermia when given every 8 weeks versus 12 weeks; four implants of 7-alpha-methyl-19-nortestosterone (MENT) were more effective than two MENT implants. Several trials showed promising efficacy in terms of percentages with azoospermia. Three examined desogestrel and testosterone preparations or etonogestrel (metabolite of desogestrel) and testosterone, and two examined levonorgestrel and testosterone. AUTHORS' CONCLUSIONS No male hormonal contraceptive is ready for clinical use. Most trials were small exploratory studies. As a result, their power to detect important differences was limited and their results imprecise. In addition, the definition of oligozoospermia has been imprecise or inconsistent. To avoid bias, future trials need more attention to the methodological requirements for randomized controlled trials. More trials with adequate power would also be helpful.
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Affiliation(s)
- D A Grimes
- Family Health International, Clinical Research, Post Office Box 13950, Research Triangle Park, North Carolina 27709, USA.
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28
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Page ST, Amory JK, Anawalt BD, Irwig MS, Brockenbrough AT, Matsumoto AM, Bremner WJ. Testosterone gel combined with depomedroxyprogesterone acetate is an effective male hormonal contraceptive regimen and is not enhanced by the addition of a GnRH antagonist. J Clin Endocrinol Metab 2006; 91:4374-80. [PMID: 16940442 DOI: 10.1210/jc.2006-1411] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
INTRODUCTION Exogenous androgens plus progestins can be used to suppress spermatogenesis, resulting in effective male hormonal contraception; however, induction of azoospermia can require 3-6 months, and these methods require injectable or implantable androgens. We hypothesized that testosterone (T) transdermal gel (T gel) could be combined with a depot formulation of the progestin, depomedroxyprogesterone acetate (DMPA), with or without the potent GnRH antagonist, acyline, to suppress spermatogenesis conveniently, rapidly, and reversibly. OBJECTIVES The objectives of the study were: 1) to determine the rate of severe oligospermia (< or = 1 million sperm/ml) using T gel+DMPA; and 2) to determine whether the addition of acyline to T gel+DMPA during the first 12 wk of the regimen would accelerate and improve suppression of spermatogenesis. METHODS Forty-four healthy men, ages 18-55 yr, were randomized to T gel (100 mg daily)+DMPA (300 mg/3 months) or acyline (300 microg/kg.2 wk x 12 wk)+T gel+DMPA. Thirty-eight men completed the 24-wk treatment protocol. RESULTS All men had dramatic suppression of spermatogenesis; 90% of the subjects became severely oligospermic, a rate comparable to implantable and injectable T+progestin combinations. The addition of acyline did not significantly accelerate spermatogenic suppression or improve rates of severe oligospermia. There were no serious adverse events, and there were minimal changes in weight, serum lipids, and prostate-specific antigen. CONCLUSIONS The combination of T gel+DMPA is a promising new regimen in male contraception. The addition of the GnRH antagonist acyline, as part of an induction phase in a male contraception regimen, has limited clinical utility. Additional studies using T gel for male contraception are warranted.
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Affiliation(s)
- Stephanie T Page
- Department of Medicine, University of Washington, Seattle, Washington 98195, USA.
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Abstract
There is a need to develop new contraceptives, particularly for men whose current choices are suboptimal in terms of effectiveness and ease of reversibility. Recent surveys indicate that men and their partners would be willing to rely on male hormonal contraceptives. Male hormonal contraception works by reversibly suppressing sperm production. Testosterone in combination with progestins or gonadotropin-releasing hormone antagonists induces profound and consistent sperm suppression. Asian men are more susceptible to the suppressive effects of testosterone given alone, even if they may benefit from the addition of an adjunctive agent to obtain optimal contraceptive protection. The aim of this review is to comment on the recent relevant achievements in the field.
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30
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Meriggiola MC, Cerpolini S, Bremner WJ, Mbizvo MT, Vogelsong KM, Martorana G, Pelusi G. Acceptability of an injectable male contraceptive regimen of norethisterone enanthate and testosterone undecanoate for men. Hum Reprod 2006; 21:2033-40. [PMID: 16731547 DOI: 10.1093/humrep/del094] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND We assessed attitudes towards and acceptability of male hormonal contraception among volunteers participating in a clinical trial of a prototype regimen, consisting of progestin and testosterone injections. METHODS After completing screening, eligible men were randomly assigned to the no-treatment group (n = 40) or to receive injections of norethisterone enanthate and testosterone undecanoate or placebo at different intervals (n = 50) according to a blocked randomization list. They underwent self-administered questionnaires. RESULTS The average age of the participants was approximately 28 years; most were involved in a stable relationship and had no children. Ninety-two percentage of the respondents thought that men and women should share responsibility for contraception and 75% said they would try a hormonal contraceptive if available. At the end of the treatment phase, 66% of the participants said that they would use such a method, and most rated its acceptability very highly; none reported it to be unacceptable. The injections themselves were indicated as the biggest disadvantage. No significant changes in sexual function or mood states were detected among the men who underwent hormone injections. CONCLUSIONS The contraceptive tested in this study was well accepted by the participants over the course of 1 year.
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Affiliation(s)
- M Cristina Meriggiola
- Obstetrics and Gynecology Unit, University of Bologna, S. Orsola Hospital, Bologna, Italy.
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Matthiesson KL, McLachlan RI. Male hormonal contraception: concept proven, product in sight? Hum Reprod Update 2006; 12:463-82. [PMID: 16597629 DOI: 10.1093/humupd/dml010] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Current male hormonal contraceptive (MHC) regimens act at various levels within the hypothalamic pituitary testicular axis, principally to induce the withdrawal of the pituitary gonadotrophins and in turn intratesticular androgen production and spermatogenesis. Azoospermia or severe oligozoospermia result from the inhibition of spermatogonial maturation and sperm release (spermiation). All regimens include an androgen to maintain virilization, while in many the suppression of gonadotrophins/spermatogenesis is augmented by the addition of another anti-gonadotrophic agent (progestin, GnRH antagonist). The suppression of sperm concentration to 1 x 10(6)/ml appears to provide comparable contraceptive efficacy to female hormonal methods, but the confidence intervals around these estimates remain relatively large, reflecting the limited number of exposure years reported. Also, inconsistencies in the rapidity and depth of spermatogenic suppression, potential for secondary escape of sperm into the ejaculate and onset of fertility return not readily explainable by analysis of subject serum hormone levels, germ cell number or intratesticular steroidogenesis, are apparent. As such, a better understanding of the endocrine and genetic regulation of spermatogenesis is necessary and may allow for new treatment paradigms. The development of an effective, consumer-friendly male contraceptive remains challenging, as it requires strong translational cooperation not only between basic scientists and clinicians but also between public and private sectors. At present, a prototype MHC product using a long-acting injectable testosterone and depot progestin is well advanced.
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Affiliation(s)
- Kati L Matthiesson
- Department of Obstetrics and Gynaecology, Prince Henry's Institute of Medical Research, Monash University, Monash Medical Centre, Clayton, Victoria 3168, Australia.
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