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A condom sealed in typical packaging
An unrolled latex condom
Condoms in many colors
type twisted condom
type spiral condom
type sensitive condom
A condom made from animal hide circa 1900
How to put on a condom
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A condom is a device, usually made of latex,
or more recently polyurethane, that is used during sexual intercourse.
It is put on a male partner's penis, for the purpose of preventing
pregnancy and/or transmission of sexually transmitted diseases (STDs)
such as gonorrhea, syphilis and HIV.
Overview
Male condoms are packaged in a rolled-up form, and are designed to
be applied to the tip of the penis and then rolled over the erect
penis. They are most commonly made from latex, but are also available
in other materials. As a method of contraception, condoms have the
advantage of being easy to use, having few side-effects, and of offering
protection against sexually transmitted diseases. With proper knowledge
and application technique - and use at every act of intercourse -
condom users experience a 2% per-year pregnancy rate. Condoms may
be combined with other forms of contraception (such as spermicide)
for greater protection.
Some couples find that putting on a male condom interrupts sex, although
others incorporate condom application as part of their foreplay. Some
men and women find the physical barrier of a condom dulls sensation.
Advantages of dulled sensation can include prolonged erection and
delayed ejaculation.
History
An Egyptian drawing of a condom being worn has
been found to be 3,000 years old. It is unknown, however, if the Egyptian
pictured wearing the device intended to use it for contraception,
or for ritual purposes.
In 16th century Italy, Gabrielle Fallopius authored the first-known
published description of condom use for disease prevention. He recommended
soaking cloth sheaths in a chemical solution and allowing them to
dry prior to use.
The oldest condoms found (rather than just pictures or descriptions)
are from 1640, discovered in Dudley Castle in England. They were made
of animal intestine, and it is believed they were used for STD prevention.
In 19th century Japan, both leather condoms and condoms made of tortoise
shells or horns were available.
The rubber vulcanization process was patented by Charles Goodyear
in 1844, and the first rubber condom was produced in 1855. These early
rubber condoms were 1-2mm thick and had seams down the sides. Although
they were reusable, these early rubber condoms were also expensive.
Distribution of condoms in the United States was limited by passage
of the Comstock Law in 1873. This law prohibited transport through
the postal service of any instructional material or devices intended
to prevent pregnancy. Condoms were available by prescription, although
legally they were only supposed to be prescribed to prevent disease
rather than pregnancy. The Comstock Law remained in force until it
was largely overturned by the U.S. Supreme Court in 1936.
In 1912, a German named Julius Fromm developed a new manufacturing
technique for condoms: dipping glass molds into the raw rubber solution.
This enabled the production of thinner condoms with no seams. Fromm's
Act was the first branded line of condoms, and Fromms is still a popular
line of condoms in Germany today. By the 1930s, the manufacturing
process had improved to produce single-use condoms almost as thin
and inexpensive as those currently available.
Condoms were not made available to U.S. soldiers in World War I, and
a significant number of returning soldiers carried sexually transmitted
infections. During World War II, however, condoms were heavily promoted
to soldiers, with one film exhorting "Don't forget — put it on before
you put it in." In part because condoms were readily available, soldiers
found a number of non-sexual uses for the devices, many of which continue
to be utilized to this day.
Materials................................................................................
Latex
Most modern condoms are made of latex. This material has outstanding
elastic properties. Tensile strength exceeds 30 MPa. Condoms may be
stretched in excess of 800% before breaking. Natural latex condoms
have a minimum thickness of 0.046 mm.
Some latex condoms are lubricated at the manufacturer with a small
amount of nonoxynyl-9, a spermicidal chemical. According to Consumer
Reports, spermicidally lubricated condoms have no additional benefit
in preventing pregnancy, have a shorter shelf life, and may cause
urinary-tract infections in women. nonoxynyl-9 was once believed to
offer additional protection against STDs (including HIV) but recent
studies have shown the opposite to be the case. The World Health Organization
says that spermicidally lubricated condoms should no longer be promoted.
However, they recommend using a nonoxynol-9 lubricated condom over
no condom at all. In contrast, application of separately packaged
spermicide is believed to increase the contraceptive efficacy of condoms.
Polyurethane
Polyurethane condoms can be thinner than latex condoms, with some
polyurethane condoms only 0.02 mm thick.
Polyurethane can be considered better than latex in several ways:
it conducts heat better than latex, is not as sensitive to temperature
and ultraviolet light (and so has less rigid storage requirements
and a longer shelf life), can be used with oil-based lubricants, is
less allergenic than latex, and does not have an odor.
However, polyurethane condoms are more likely to slip or break than
latex, are more expensive, and may not be as effective in protecting
against STDs (large clinical trials have not been performed).
Lambskin
Condoms made from one of the oldest
condom materials, labeled "lambskin" (made from lamb intestines) are
still available. They have a greater ability to transmit body warmth
and tactile sensation, when compared to synthetic condoms, and are
less allergenic than latex. However, there is a great risk of transmitting
STDs because of pores in the material. While the pores are not large
enough to allow sperm through, much smaller bacteria and viruses may
easily slip in and out between the condom.
Invisible
The Invisible Condom, developed at Universit? Laval in Qu?bec, Canada,
is a gel that hardens upon increased temperature after insertion into
the vagina or rectum. In the lab, it has been shown to effectively
block HIV and herpes simplex virus. The barrier breaks down and liquefies
after several hours. The invisible condom is in the clinical trial
phase, and has not yet been approved for use.
Spray-on
As reported on Swiss television news Schweizer Fernsehen on November
29, 2006, the german scientist Jan Vinzenz Krause of the Institut
f?r Kondom-Beratung ("Institute for Condom Consultation") in germany
recently developed a spray-on condom and is test-marketing it. Krause
says the advantages to his spray-on condom, which is reported to dry
in about 5 seconds, is that it is perfectly formed to each penis.
Form
In recent decades, condom makers have diversified in colors, shapes,
and thicknesses. Flavors or designs thought to have stimulating properties
are sometimes added. Such stimulating properties include enlarged
tips or pouches to fit the glans penis better and textured surfaces
such as ribbing or studs (small bumps). Many condoms have spermicidal
lubricant added, but it is not an effective substitute for separate
spermicide use. Most condoms have a reservoir tip, making it easier
to leave space for the man's ejaculate. Condoms also come in different
sizes, from magnum to snug.
Effectiveness...........................................................................
In preventing pregnancy
The effectiveness of condoms, as of most forms of contraception, can
be assessed two ways: method effectiveness and actual effectiveness.
The method effectiveness is the proportion of couples correctly and
consistently using the method who do not become pregnant. Actual effectiveness
is the proportion of couples who intended that method as their sole
form of birth control and do not become pregnant; it includes couples
who sometimes use the method incorrectly, or sometimes not at all.
Rates are generally presented for the first year of use. Most commonly
the Pearl Index is used to calculate effectiveness rates, but some
studies use decrement tables.
Article Source: http://en.wikipedia.org/wiki/Condom |
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Female condom |
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