Reversible Inhibition of Sperm Under Guidance (RISUG) is also starting to get recognition in the United States. Men receive an injection of chemicals that form a gel along the vas deferens, the pathway that transports sperm. The gel can last for 10 to 15 years. During that time it both reduces the number of sperm making the trip, and also physically disables the ones that do make it safely through the passageway.
The major concern with vasectomies, the only form of male contraception other than condoms, is that they are not always reversible, a risk many men are unwilling to take. According to the researchers involved, RISUG solves that problem. At any point the man can receive a second injection that dissolves the sperm-blocking gel and reverses the contraceptive.
The RISUG method has been in clinical trials in India for several years, and recently U.S. researchers took notice and will start testing it out here. Elaine Lissner, director of the Male Contraception Information Project in San Francisco, bought the rights to the technique and will repeat the clinical trial process in the U.S. in hopes of readying it for FDA approval.
Now that baby boomers and post-baby boomers make up the majority of men needing contraception, 13% to 80% of men (depending on the country and study) express interest in using a new male method. A recent study of over 9,000 men in nine countries on four continents showed that more than 60% of men in Spain, Germany, Mexico and Brazil expressed willingness to use a new male contraceptive. These men would like to relieve their partners of some of the contraceptive burden in their relationship or would simply like a more reliable backup to condoms.