Washington: Whenever we speak about contraception for men, the only choices that pop up in our mind are condoms or vasectomy. But looks like a new product will soon be added to the list, which has been this way for more than a century now.
The product, called Vasalgel, a new injectable gel that blocks sperm inside the body, has proved effective in male rhesus monkeys, according to research published in the open access journal Basic and Clinical Andrology.
This contraceptive gel, which has the potential to be a reversible alternative to vasectomy, prevents sperm from leaving the body while allowing seminal fluid to pass through.
It was earlier trialled in rabbits in 2016. Dr Catherine VandeVoort, lead author from the California National Primate Research Centre, said, "Our research shows that Vasalgel placement into the vas deferens produces reliable contraception in mature male rhesus monkeys as shown by the lack of pregnancies in reproductively viable females with which the males were housed. Importantly, we show that the method of Vasalgel placement is safe and produced fewer complications than usually occur with a vasectomy."
Adding, "Vasalgel shows real promise as an alternative to vasectomy because research in rabbits has previously shown the product to be reversible. Although it is possible to reverse a vasectomy, it is a technically challenging procedure and patients often have very low rates of fertility following reversal."
The researchers selected 16 adult male monkeys for surgery that involved injection of Vasalgel into the vas deferens. The monkeys were then monitored closely for seven days for healthy recovery before being introduced back into their normal group housing. This consisted of large outdoor enclosures containing between 10-30 monkeys that included male and female infants, juveniles and adults.
Each group had between one and three males that had been administered Vasalgel. The males were housed with their groups for at least one breeding season (approximately six months) and the authors report that no conceptions occurred. The expected pregnancy rate for sexually mature females in similar housing is approximately 80 percent per breeding season, according to the researchers.
One monkey out of the 16 that received Vasalgel showed signs of sperm granuloma (a hard build-up of sperm in the vas deferens) as a result of the injection. This is a common complication following a vasectomy, occurring in around 60 percent of cases in humans, according to the researchers. Discomfort or serious side effects caused by sperm granuloma are rare following a vasectomy. The researchers also state that the typical rate of sperm granuloma in male rhesus monkeys that have undergone vasectomy is around 15 percent.
Now the researchers behind the product hope that it could get trials in humans within a few years.