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What would it take to come up with a way to sterilize pets without doing surgery? A wealthy inventor who happens to be a retired surgeon is hoping the answer is: "a $75 million prize."
Animal-lover Gary Michelson has pledged $25 million to the person or group that comes up with a safe, one-time non-surgical way of sterilizing male and female cats and dogs, and will give up to $50 million more to support research on promising approaches.
In addition to pets in the developed world, the philanthropist and his foundation are concerned about street animals, which often only live a few years. We are telling researchers studying multi-year male contraceptives about this opportunity and encouraging them to consider applying for the funds, since their work could benefit both men and animals. "'We're completely agnostic regarding the approach,' says the executive director of the foundation giving the prize. 'We'll consider anything. We really believe if cutting-edge technologies are applied we can solve this.'"
Read more:
Inventor Michelson offers $75M for a way to sterilize pets
The Chinese government has long supported male contraception research, and Chinese researchers were the ones who developed the "No-Scalpel Vasectomy" procedure that is now the worldwide gold standard. What’s being studied in terms of potentially reversible methods? (Thanks to Drs. Yi-Qun Gu and Kirsten Vogelsong for getting this information!)
Hormonal male contraceptives
Results from a big study on testosterone undecanoate (TU) alone as a hormonal male contraception will soon be published. 1,045 men at 10 participating centers in China took monthly shots of TU, which is a form of testosterone that is available in Europe and China but not the US. Researchers have finished the study and follow-up; we’ll update you when their results are published. Testosterone-only approaches have proven quite effective in Asian men in previous smaller studies, while a testosterone plus progestin regime is now recommended for studies in non-Asian men.
Chinese design of the Intra Vas Device (IVD)
This study of 1,516 men at 4 centers in China, sponsored by the State Family Planning Committee, is going well. The Chinese IVD is a tiny, flexible urethane tube; one device is implanted in each vas deferens (the sperms’ passageway). The IVD tube is lined with a medical-grade nylon mesh that acts as a filter to trap sperm, and a small hole in the tube allows the fluid in the vas to pass through while the sperm stay trapped. Researchers hope this design will result in less back-pressure and increase the chances of pregnancy if a man wants the plugs removed. The current study includes IVD insertion and then checks on men at 3 months, 1 year and 2 years. Partial results at 1 year were published in 2006; they showed that the IVD was slightly less effective at blocking sperm than no-scalpel vasectomy (94% vs. 98-99%), but had a lower risk of side effects such as swelling or pain. Two-year follow-up is now finished and the data are being analyzed. We look forward to the results, and to hearing whether the earlier 94% success rate based on sperm counts was enough to prevent pregnancies throughout the 2 years of the study. This would be particularly good news, since development of the US IVD design seems to be on hold.
Trypterygium wilfordii
This herb is commonly used in Chinese medicine to treat autoimmune diseases. Extracts of this herb are on the market in pill form (“lei gong teng pian”) and were shown to make men temporarily infertile in Chinese studies in the late 1980s. The dose used to treat autoimmune diseases is 3 times the contraceptive dose. Any possibility of lowering immune activity would be a worry for healthy men, so the World Health Organization started to analyze purified derivatives to see whether one might have contraceptive effect with no immune effect. The first one didn’t work out, and they ran out of money. There’s no money to re-start the time-consuming process of testing the other 5 active derivatives. Since there’s no money for looking for the perfect extract, how about testing the existing pills to see whether the contraceptive dose is free of immune effect? That recently got more difficult, too. Research in China on the commercially available pills now faces much stricter drug regulations that make it hard to test new uses of already-approved drugs. Until such studies are done, Trypterygium wilfordii extracts should only be used by men with autoimmune conditions (such as psoriasis and arthritis) and under the supervision of an experienced Chinese medicine specialist.
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At a recent meeting of male contraceptive experts, Dr. Jacqui Darroch – formerly of the Guttmacher Institute and the Gates Foundation – spoke about male contraceptive development from an international perspective. She summarized a wealth of data from developing countries using 40 years of Demographic and Health Survey results. She shows that the average desired family size of men and women around the world has dropped. While contraceptive use has increased in the last decades, unmet need for contraception remains persistent. With population size growing, demand for reliable family planning options will only continue to rise. Finally, dissatisfaction with current methods and fear of side effects have grown consistently as a reason for non-use. All of these observations support the need for new family planning options.
Dr. Darroch summarizes:
- “Men have a stake in fertility control; they have a long history of contraceptive use, but, with the development of effective female-used methods, most of method use has been passed to women, relieving men and/or pushing them out from the sphere of contraception. Development of new methods for men can change this.
- "Patterns of contraceptive use vary widely, by personal, relationship, service setting and cultural contexts. New methods for men are likely to be integrated into lifetime patterns of male- and female-used methods rather than substitute entirely for female-used methods.
- "Most contraceptive users, and most unmet need, exist in developing countries. Potential opportunities—and needs—for improved use exist among nonusers, users of traditional methods, as well as current users of male and of female methods. Dissatisfaction with currently used methods also indicates opportunities for introduction of new male methods into developed countries such as the United States.
- "Markets for new male methods will need to be activated, rather than be expected to respond to active demand as was the case when modern female-used methods were introduced in the early 1960s.
- "Motivating factors for use of new male methods are most likely to be dissatisfaction with current method options and partner encouragement or interest.
- "Problems evident in female contraceptive use are likely also to exist for male methods, including fears about health and other side effects and access problems, such as cost to users and to public funders.
- "The female-focused service system may not be easy to expand to serving males.”
Read more:
Male Fertility Control -- Where are We?
Contraception Volume 78, Issue 4 Supplement
October 2008
Edited by Michael J. Harper
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The University of Calgary student paper covers hormonal clinical trials at the University of Washington. "Clinical testing at the University of Washington shows that the success rate of male hormonal contraceptives can be as high as 100 per cent, with subject's test results showing a sperm count of zero, but this is only if the treatments have any impact. These studies also reveal that 10-15 per cent of males do not respond to treatment, which is a high percentage... A survey by the Kaiser Family Foundation in the U.S. found that 71 per cent of American men would consider an alternative form of birth control and 66 per cent of those surveyed said they would try the male pill... Those in monogamous relationships with sensitivities to condoms or for those women who can't take the pill this is a great alternative... Until there is a higher success rate and a greater demand, we may be waiting longer than once thought for this new and innovative product."
Dudes on the pill: The coming of male birth control
University of Calgary Gauntlet, 23 October
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Editors
Elaine Lissner, Director of the Male Contraception Information Project (MCIP)
Email: info@NewMaleContraception.org
MCIP is entirely nonprofit and works in three areas: raising public awareness of promising nonhormonal male contraceptives, advocating increased and expedited government research, and serving as a resource for journalists who wish to write about the subject.
Kirsten Thompson, Director of the Male Contraception Coalition (MCC)
Email: info@MaleContraceptives.org
The Coalition’s objectives are to speed the development of new male contraceptives through increased legislative and institutional support, to raise funds for applied male contraception research and development, and to educate the public about the work of the research community.
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