Vas-occlusive contraception is an experimental

Experiment

An experiment is a methodical procedure carried out with the goal of verifying, falsifying, or establishing the validity of a hypothesis. Experiments vary greatly in their goal and scale, but always rely on repeatable procedure and logical analysis of the results...

 male contraceptive

Male contraceptive

Male contraceptives include condoms, withdrawal , and vasectomy. In other animals, castration is commonly used for contraception...

 method that is not yet approved for general use. Proposed methods of vas-occlusive contraception attempt to prevent sperm

Spermatozoon

A spermatozoon is a motile sperm cell, or moving form of the haploid cell that is the male gamete. A spermatozoon joins an ovum to form a zygote...

 from traveling down the vasa deferentia. Potential methods include clips, plugs, valve

Valve

A valve is a device that regulates, directs or controls the flow of a fluid by opening, closing, or partially obstructing various passageways. Valves are technically pipe fittings, but are usually discussed as a separate category...

s, and other devices.

The intra vas device (IVD), analogous to the intrauterine device

Intrauterine device

A copper IUD is a type of intrauterine device. Most IUDs have a plastic T- or U-shaped frame which is wrapped in copper wire, with the exception of Gynefix, which is a plastic string with several copper beads, affixed to the fundus of the uterus...

 (IUD) for women, is meant to be a reversible alternative to a vasectomy

Vasectomy

Vasectomy is a surgical procedure for male sterilization and/or permanent birth control. During the procedure, the vasa deferentia of a man are severed, and then tied/sealed in a manner such to prevent sperm from entering into the seminal stream...

. The device consists of a set of flexible, hollow silicone

Silicone

Silicones are inert, synthetic compounds with a variety of forms and uses. Typically heat-resistant and rubber-like, they are used in sealants, adhesives, lubricants, medical applications , cookware, and insulation....

 plugs, each about a millimetre in diameter and 2.5 cm long. The IVDs are inserted into the vas deferens

Vas deferens

The vas deferens , also called ductus deferens, , is part of the male anatomy of many vertebrates; they transport sperm from the epididymis in anticipation of ejaculation....

 and block the flow of sperm from the testes to the seminal vesicle

Seminal vesicle

The seminal vesicles or vesicular glands are a pair of simple tubular glands posteroinferior to the urinary bladder of male mammals...

s.

Progress

, human clinical trial

Clinical trial

Clinical trials are a set of procedures in medical research and drug development that are conducted to allow safety and efficacy data to be collected for health interventions...

s are being performed to evaluate its effectiveness as a contraceptive. One version is currently in research and development by Shepherd Medical in Vancouver

Vancouver

Vancouver is a coastal seaport city on the mainland of British Columbia, Canada. It is the hub of Greater Vancouver, which, with over 2.3 million residents, is the third most populous metropolitan area in the country,...

. Another version currently being researched in China

China

Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

 is an elastomer

Elastomer

An elastomer is a polymer with the property of viscoelasticity , generally having notably low Young's modulus and high yield strain compared with other materials. The term, which is derived from elastic polymer, is often used interchangeably with the term rubber, although the latter is preferred...

 plug device, using medical-grade polyurethane

Polyurethane

A polyurethane is any polymer composed of a chain of organic units joined by carbamate links. Polyurethane polymers are formed through step-growth polymerization, by reacting a monomer with another monomer in the presence of a catalyst.Polyurethanes are...

 (MPU) and silicone rubber

Silicone rubber

Silicone rubber is an elastomer composed of silicone—itself a polymer—containing silicon together with carbon, hydrogen, and oxygen. Silicone rubbers are widely used in industry, and there are multiple formulations...

 (MSR) injected as a liquid.

The U.S. Food and Drug Administration (FDA) approved human clinical trials for the intra-vas device in 2006.

Side effects

The procedure is expected to have similar side effects to vasectomy, such as formation of sperm antibodies

Antibody

An antibody, also known as an immunoglobulin, is a large Y-shaped protein used by the immune system to identify and neutralize foreign objects such as bacteria and viruses. The antibody recognizes a unique part of the foreign target, termed an antigen...

.

External links

• Press release on Dr. Pollock's website
• Another article
• Birth control for men promising — has some extra details and information about current trials
• Reversible male implant may be future of contraception
• Birth control breakthrough — But will it hold mass appeal? (picture appears to be a mistake)
• Information about Chinese versions — using MPU medical-grade polyurethane, and MSR medical-grade silicone rubber
• Information about a silicone rubber version, the shug — anchored with a suture
• Male contraceptive trial to be expanded — "A US trial of a new male contraceptive is being expanded after men rushed to sign up."