A condom sealed in typical packaging
An unrolled latex condom
Condoms in many colors
type twisted condom
type spiral condom
type sensitive condom
How to use
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.
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.
For all forms of contraception, actual effectiveness is lower than
method effectiveness, due to several factors:
- mistakes on the part of those providing instructions on how to
use the method
- mistakes on the part of the method's users
- conscious user non-compliance with method.
For instance, someone using oral forms of hormonal birth control
might be given incorrect information by a health care provider as
to the frequency of intake, or by mistake not take the pill one
day, or simply not bother to go to the pharmacy on time to renew
the prescription. The method failure rate of condoms is 2% per
year.[1] The actual pregnancy rates among condoms users vary
depending on the population being studied, with rates of 10-18%
per year being reported.
Article Source: http://en.wikipedia.org/wiki/Condom |
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