Surveys show that most men would be open to trying new male contraceptives if any were available. Now, a recent study involving rhesus monkeys suggests that Vasalgel (TM) may be an eventual non-hormonal contraceptive option for men.
Vasalgel, a high molecular weight polymer, becomes a hydrogel when injected into the vas deferens, where it effectively blocks the passage of sperm. In earlier studies with rabbits, the contraceptive function of Vasalgel was quickly reversed just by using a sodium bicarbonate solution to flush the gel out.
In the rhesus study Vasalgel injections were given to 16 adult male monkeys. After a seven-day recovery period, the males were put into outdoor group housing units that also held three to nine females with successful breeding histories. Each male was monitored through at least one breeding season, and seven of them lived with the females for two years.
The researchers report no conceptions occurred following the Vasalgel injections. Complications were minor, one being owed to a misplaced injection, and the occurrence of sperm granulomas in the Vasalgel monkeys was less than in the control group that underwent vasectomies.
Though vasectomies are considered a simple procedure for humans, they are more complex and complication prone for monkeys; so the veterinarians working on this study were pleased with the results. Vasalgel may provide caretakers of captive primates a simple, cost-effective way to manage a colony’s reproductive rates.
Vasalgel may also offer human males a hormone-free way to manage their own reproductive potential. Preparations are in the works for initial human clinical trials. The first study will explore the effectiveness of Vasalgel for preventing human conception, while later research will look at the efficacy of flushing out the gel to reestablish sperm flow.
Source: Science Daily
Photo credit: Christian Bonzalez