February 1, 2013 (Vol. 33, No. 3)

Not Just a Reproductive Issue, More Choices Are a Matter of Social Justice and Equality

Despite many years of research, we still don’t have any new contraceptive options for men. Many women might welcome the opportunity to share contraceptive responsibilities with their partners, and family planning discussions between men and women might change in unexpected ways. However, while women have a dazzling variety of contraceptives to choose from (Table), men still have only two modern methods: condoms or vasectomy.

Condoms are commonly used by young men who have not yet begun living with a steady partner, or by couples who are able to deal with the inconveniences of condoms. However, most men consider condoms to be uncomfortable and clumsy to use. Some men consider female condoms more comfortable and acceptable, but they are more expensive and not as widely available, and neither type of condom is considered highly effective in terms of pregnancy prevention.

Vasectomy is only used after a couple has completed childbearing. While vasectomy can be surgically reversed, reversal procedures are expensive and lead to pregnancy in only about 40% to 50% of cases.

David C. Sokal, M.D.

There is currently no convenient, reliable, and reversible method for men. As an issue of social justice and equality, men deserve more options.

There are some interesting potential social consequences and advantages that might come from a new male method, e.g., a male pill. Men would be more empowered to control their own fertility and might feel more responsible for pregnancies.

In addition, while many reversible female methods are highly effective, they all have side effects. The best way for women to avoid the side effects of female contraceptive methods might be for their male partners to have some new choices. If a woman has problems with a particular method, her partner might be able to help out, while she considers switching to another method. Some men might take primary responsibility for contraception.

From a social/political point of view, a male contraceptive might be more acceptable to some people because it would un-ambiguously eliminate concerns about whether a particular type of family planning acts before or after conception. Enforcement of child support obligations might be better accepted because men would have had a way to avoid fatherhood.

Researchers have worked for many years to develop and commercialize a male hormonal contraceptive, but without success. A number of different types of hormones and hormone combinations have been tried, and researchers have found that a combination of an androgen and a progestin is the most effective approach. But the research is inevitably slow.

It typically takes 10 to 20 weeks for a male hormonal method to suppress fertility, because sperm production is a 10 week process. Even if one halts production of new sperm, the sperm that are already in the pipeline will reach maturity and maintain a man’s fertility until they are exhausted. While testosterone is effective at reducing sperm counts to a level that will prevent pregnancies, there is concern about side effects, such as acne or changes in mood.

Contraceptive Methods for Women and Men

Promising Developments

In recent years, biotechnology and medical science have made tremendous advances, suggesting the possibility of some innovative nonhormonal approaches that would be highly effective with minimal side effects and, ideally, a more rapid onset of action than hormonal methods.

There are some promising leads: S. Kean recently reported in Science on researchers working to halt sperm production; M. O’Rand et al., are working to immobilize sperm; Amobi N et al., are modifying muscle contractility of the vas to prevent passage of sperm; and an Indonesian team may have found a naturally occurring compound that prevents a man’s sperm from penetrating the woman’s egg.

An advantage of the methods that don’t target sperm production is the potential for a more rapid onset of effective contraception, perhaps days or even hours instead of months, and a lack of impact on testosterone production. There is some encouraging unpublished data on some of these new leads, and one or more of them might turn out to be effective enough to be approved by the FDA if there were adequate funding to support their development. More information on these potential new methods is available at www.newmalecontraception.org and in the reference list accompanying this article.

Proposed Prize Incentive

The Michelson Foundation has offered a $25 million prize for development of new contraceptives for cats and dogs (http://michelson.foundanimals.org/michelson-prize), and has pledged up to $50 million in grants to fund researchers working to win the prize. However, there is no similar effort for human males.

Given the relative lack of funding for new male contraceptives, it might be interesting if the X-Prize Foundation (www.xprize.org) became interested in this topic and offered a prize for development of a new male contraceptive. Given the impact of human population on the environment and of unintended pregnancies on women’s health and on couples’ prospects for escaping poverty worldwide, the prize should be larger than the Michelson Prize for pet contraception.

If such a prize were offered, it could be called the “Y Prize,” for the Y chromosome. The rules for such a prize might be something like this:

  1. Product profile: convenient, low-cost, nonhormonal, nonsurgical, reversible method.
  2. Obtain Phase II clinical trial data with effectiveness greater than 95% including data from at least 100 couples for at least 12 months.
  3. Follow-up of the men in the Phase II trial must be completed by Dec. 2020.
  4. Obtain FDA agreement by December 2021 to proceed to a Phase III clinical trial.
  5. Agree to a public sector pricing policy, to make sure that the new method is affordable.
  6. Prize: $50 million, which is twice the amount of the Michelson Prize for a new contraceptive method for cats and dogs.

David C. Sokal, M.D. ([email protected]), recently retired from a career that included research on vasectomy effectiveness and related topics.

Amobi, N. I. B., Guillebaud, J., & Smith, I. C. H. (2012). Perspective on the role of P2X-purinoceptor activation in human vas deferens contractility. Experimental physiology, 97(5), 583–602. doi:10.1113/expphysiol.2011.063206
“ASRM (Practice Committee of American Society For Reproductive Medicine)”. (2008). Vasectomy reversal. Fertility and sterility, 90(5 Suppl), S78–82. doi:10.1016/j.fertnstert.2008.08.097
Campo-Engelstein, L. (2011). No More Larking Around! Hastings Center Report, 5(5), 22–26.
Grimes, D. A., Lopez, L. M., Gallo, M. F., Halpern, V., Nanda, K., & Schulz, K. F. (2012). Steroid hormones for contraception in men. Cochrane database of systematic reviews (Online), 3, CD004316. doi:10.1002/14651858.CD004316.pub4
Indonesian Plant Shows Promise for Male Birth Control | PBS NewsHour | July 20, 2011. (n.d.). Retrieved December 18, 2012, from http://www.pbs.org/newshour/bb/health/july-dec11/birth_07-18.html
Kean, S. (2012). Contraception research. Reinventing the pill: male birth control. Science (New York, N.Y.), 338(6105), 318–20. doi:10.1126/science.338.6105.318
O’Rand, M. G., Widgren, E. E., Hamil, K. G., Silva, E. J., & Richardson, R. T. (2011). Epididymal protein targets: a brief history of the development of epididymal protease inhibitor as a contraceptive. Journal of Andrology, 32(6), 698–704. doi:10.2164/jandrol.110.012781

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