|
|
The Chinese government has long supported male contraception research, and the Chinese "No-Scalpel Vasectomy" procedure is now recognized as the worldwide gold standard. This month we update you on potential non-permanent methods. Thanks to Dr. Yi-Qun Gu, of China’s National Research Institute for Family Planning, and Dr. Kirsten Vogelsong, of the World Health Organization, for connecting us with this information!
Male hormonal contraceptives
Results of a collaborative research effort between the Chinese government and the World Health Organization will soon be published. The study used intramuscular depot testosterone undecanoate (TU) injections every 8 weeks. Recruitment ran December 2001 - December 2002; a total of 1,045 subjects from 10 participating centers in China participated. We’ll let you know when the results are published. Another paper on data this study collected was published earlier this year. It concluded that gene mutations for hormone receptors were unrelated to non-suppression of spermatogenesis in this population. Testosterone-only approaches have proven quite effective in Asian men, while a testosterone plus progestin regime is now recommended for non-Asian men.
Chinese design of the Intra Vas Device (IVD)
This phase II clinical trial of 1,516 men at 4 centers in China is sponsored by the State Family Planning Committee of China and is going well. The Chinese IVD is a tiny, flexible urethane tube; one device is implanted in each vas deferens. The tube is lined with a medical-grade nylon mesh that acts as a sieve to capture sperm, and a small hole near allows the fluid in the vas to pass through while the sperm stay trapped. The intent of the design is to reduce pressure on the epididymis and increase the chances of successful reversal. The ongoing trial includes IVD insertion and follow-up 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 than no-scalpel vasectomy (94% vs. 98-99%), but had a lower risk of side effects. Two-year clinical follow-up has now been completed and the data are being analyzed. We look forward to the results, and to hearing whether the earlier 94% success rate based on semen analysis was enough to prevent pregnancies throughout the study’s 2 years.
Trypterygium wilfordii
Extracts of this herb, commonly used in Chinese medicine, are commercially available in pill form and have been shown to produce reversible infertility in men. Because higher doses of the herb extract—about 3x the contraceptive dose—are used to treat autoimmune diseases, a derivative of the herb without autoimmune effects has been sought. The World Health Organization collaborated on analysis of purified derivatives, but this work foundered when the first of the derivatives didn't work out and money ran short. No funds are immediately forthcoming to re-start the time-consuming process of testing the other 5 active compounds. In the meantime, Trypterygium wilfordii pills should not be used as contraceptives except by men with autoimmune conditions (such as psoriasis and arthritis) under the supervision of a Chinese medicine specialist, until larger studies determine whether the a contraceptive dose is free of immune action. Further research in China has been stymied by recent changes in drug research regulations, which make testing new uses of already-marketed drugs more difficult. This research awaits a new team to carry it forward.
Return to the top
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
Return to the top
What would it take to produce a nonsurgical sterilant for animals? A wealthy inventor who is also 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 means to sterilize male and female cats, and will devote up to $50 million more to support research on plausible approaches.
We’re encouraging researchers studying nonsurgical long-term or potentially permanent contraceptives for men to consider applying for the funds, since their work could benefit both men and animals. "'We're completely agnostic regarding the approach,' says foundation executive director Aimee Gilbreath. '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
Humanitarian Offers $75 Million for Single Dose Sterilization of Cats and Dogs
Return to the top
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
Return to the top
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.
|
