Tuesday, October 10, 2006

Plug is new contraceptive for men
By David Rose
The huge interest in trials of a possible reversible alternative to vasectomy has surprised scientists

TRIALS of a new male contraceptive are being expanded after overwhelming interest from the public.
Scientists in the United States have been taken aback by the number of men who are eager to test the method, which is potentially reversible and designed as an alternative to surgical vasectomy.
The Intra Vas Device or IVD, which is inserted via a small hole made in the scrotum, uses a tiny plug of silicone gel that blocks sperm from travelling along the each of the tubes connecting the testicles and the penis, known as the vas deferens.
In a pilot study involving 30 men the IVD was effective in preventing conception. Studies in monkeys have also shown that it is reversible.
Extensive tests are now needed to check if the method is reversible in men using the device for years rather than months.
A traditional vasectomy, where the vasa deferntia are tied or cut, can be reversed in some men, but it is designed to be permanent.
Elaine Lissner, of the non-profit Male Contraceptive Information Project in San Francisco, said: “It is a lot easier to pull the plugs out than to find the best, most expensive microsurgeon to sew a vas deferens back together. But even if you can get sperm flowing again, the chances of pregnancy go down by about 10 per cent for each year the man had the vasectomy. Only time will tell if it’s the same for IVD.”
Ms Lissner said men increasingly want to take responsibility and control for the use of contraception. A recent study of more than 9,000 men in nine countries suggested more than 60 per cent of men in countries such as Spain, Germany, Mexico and Brazil would like to relieve their partners of some of the burden of using contraception in their relationship or would like a reliable back-up to condoms.
Surgeons testing the IVD injected a silicone gel through the skin of the scrotum directly into the vas deferens, where it will block the sperm. The main concern is the build- up of pressure behind the silicone plug, which could damage the sperm production glands in the testes.
Shepherd Medical Company will begin testing its IVD next week. Originally the researchers had planned to include male volunteers from St Paul, Minnesota, but have expanded the trials because of the high demand.
All the men taking part have finished having families and would otherwise have desired a vasectomy, the researchers said. The evaluation group will test the IVD for two years.
British regulators said they were not aware of any similar trials planned.
Other scientists have been searching for less invasive and reversible male contraceptives based on hormones that could be taken in the same way as the female Pill.
Richard Anderson, of the University of Edinburgh, who has been investigating hormonal male contraceptives, said: “This would be a very attractive alternative to vasectomy. But even if it is potentially reversible after a few years, it would still not be a contraceptive that could be put in and taken out repeatedly for spacing your family, for example.”
Researchers in China are working on a mesh-like vas deferens plug that allows small amounts of sperm through, not enough to cause a pregnancy, which could get round problems from sperm build-up.
BIRTH CONTROL WITHOUT TEARS
About 18 per cent of men aged 16 to 69 have had a vasectomy, which involves cutting the vas deferens tubes between the testicles and the groin and sealing them with stitches, knots or heat
The procedure usually takes place under local anaesthetic and is not considered effective for 2-3 months. The testes and penis are not affected, so there is no change in libido, virility or ejaculation
Vasectomy was designed in the 19th century to control sections of society such as “delinquents, degenerates, drug habitués and idiots”. It came into common use for family planning in the late 1960s

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