A gel squirted into the sperm ducts of monkeys has been effective at preventing pregnancy, said a study Tuesday which offered hope of a solution for men reluctant to go under the knife for family planning.<\/p>\n
While several birth control options exist for women, the race is on for a non-surgical, long-term and reversible male contraceptive without the side effects of hormonal changes.<\/p>\n
The only short-term solutions available today are condoms, which many people complain interfere with sex, and withdrawal before ejaculation, which comes with a high risk of pregnancy.<\/p>\n
Longer term, the sole option is a vasectomy, which involves tying or cutting the sperm-conducting tubes called vas deferens. This prevents sperm from mixing with seminal fluid ejaculated during sex.<\/p>\n
Vasectomies can be reversed in some cases, but the procedure is technically challenging and leads to low rates of fertility.<\/p>\n
Researchers in the United States are developing a possible alternative, dubbed Vasalgel, which has proven effective in rabbits and now also in rhesus monkeys — more closely related and anatomically similar to humans.<\/p>\n
Vasalgel is a polymer gel injected directly into the vas deferens, creating a blockage in the tube that transports sperm from the testes out through the penis.<\/p>\n
In an experiment at the California National Primate Research Center, 16 adult male monkeys were treated. They were housed with females, and monitored for up to two years — covering at least one breeding season per animal.<\/p>\n
“Treated males have had no conceptions since Vasalgel injections,” the research team wrote in the journal Basic and Clinical Andrology<\/em>.<\/p>\n \u00a0<\/p>\n \u00a0<\/p>\n Normally, the expected pregnancy rate among females housed with males would have been about 80 percent.<\/p>\n “The presence of Vasalgel appears to be well tolerated and placement resulted in minimal complications,” the researchers wrote.<\/p>\n One monkey of the 16 had symptoms of sperm granuloma, a buildup in the vas deferens which is a common complication in about 60 percent of human vasectomies, they added.<\/p>\n Not yet tested in monkeys, the reversibility of the method was tested in earlier experiments in rabbits, when the gel was successfully flushed out with solution of sodium bicarbonate.<\/p>\n Preparations are underway for a clinical trial with Vasalgel in humans, said the Parsemus Foundation, a non-profit organization funding the product’s development.<\/p>\n The research has benefits for the monkeys as well, researchers added.<\/p>\n It is ideal to house captive rhesus monkeys in groups for their social welfare, but populations can quickly explode due to high fertility.<\/p>\n And vasectomy in monkeys is more complex than in humans, with many complications.<\/p>\n “We were impressed that this alternative worked in every single monkey, even though this was our first time trying it,” said Angela Colagross-Schouten, the project’s lead veterinarian.<\/p>\n \u00a0<\/p>\n","protected":false},"excerpt":{"rendered":" A gel squirted into the sperm ducts of monkeys has been effective at preventing pregnancy, said a study Tuesday which offered hope of a solution for men reluctant to go under the knife for family planning. While several birth control options exist for women, the race is on for a non-surgical, long-term and reversible male Read More<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[],"tags":[],"class_list":["post-152104","post","type-post","status-publish","format-standard","hentry"],"_links":{"self":[{"href":"http:\/\/healthmedicinet.com\/i\/wp-json\/wp\/v2\/posts\/152104","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/healthmedicinet.com\/i\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/healthmedicinet.com\/i\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/healthmedicinet.com\/i\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/healthmedicinet.com\/i\/wp-json\/wp\/v2\/comments?post=152104"}],"version-history":[{"count":0,"href":"http:\/\/healthmedicinet.com\/i\/wp-json\/wp\/v2\/posts\/152104\/revisions"}],"wp:attachment":[{"href":"http:\/\/healthmedicinet.com\/i\/wp-json\/wp\/v2\/media?parent=152104"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/healthmedicinet.com\/i\/wp-json\/wp\/v2\/categories?post=152104"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/healthmedicinet.com\/i\/wp-json\/wp\/v2\/tags?post=152104"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}