What Is An IUD?
An IUD is a small plastic device that is inserted into the uterus to
prevent pregnancy. The IUD is an easy, convenient, highly effective form of
contraception that does not interfere with spontaneity. The IUD requires no
daily attention, however, you should check it's placement after each period.
It must be inserted and removed at any time by a healthcare professional. It
can be removed at any time and fertility resumes immediately.
Today there are two IUD options. One has a copper band around the IUD. It
can stay inside the body for up to 10 years. The other contains a small
amount of the hormone progesterone which increases it's effectiveness and
reduces side effects, and it must be replaced annually.
Mechanisms of action
Various hypotheses have been advanced over the years about the mechanisms
of action of IUDs, including interference with sperm transport, ovum
transport or development, fertilization, and implantation. Until about 1980,
it was believed that the IUD worked mainly by causing an inflammatory
response to a foreign body in the uterus, thereby interfering with
implantation of a fertilized egg in the uterine wall. The informed consensus
now has changed.
Studies support the conclusion that Copper IUDs prevent fertilization by
reducing the number and viability of sperm reaching the egg, and by impeding
the number and movement of eggs into the uterus. It is believed that the
continuous release of copper from the coils and sleeves of the Copper T 380A
into the uterine cavity enhances the contraceptive effect of the IUD.
Effectiveness
The annual pregnancy rate of users of the Copper T 380A is well below one
per 100, within the range of implantable and injectable contraceptives and
surgical sterilization. In actual use during the first year, the Copper T
380A IUD is more effective than most other IUDs, oral contraceptives,
condoms, and barrier methods. The data in the US FDA labeling show
cumulative pregnancy rates at three, five, and eight years of 1.5, 1.9, and
2.3 per 100 users respectively. The effectiveness of the Copper T 380A IUD
was found to be related to age, with pregnancy rates decreasing for older
women.
Duration of effectiveness
The US Food and Drug Administration first approved the Copper T 380A in
1984 for a duration of four years. In 1989, based on data submitted by the
Population Council from its and WHO studies, the FDA extended the period of
efficacy to six years. On the basis of further data, in 1991 the US FDA
approved use of the Copper T 380A for eight years and in 1994 the period of
use was extended to ten years. The ten-year duration applies to the Copper T
380A IUD governed by US FDA labeling. Approvals by regulatory agencies in
other countries may apply to different models, and may stipulate different
durations of effectiveness.
Long term studies shown that the TCu-380 A is effective for at least 12
years after insertion.
Timing of insertion
The copper T 380A IUD may he inserted at any time during the menstrual
cycle, provided the women is not pregnant and has been consistently using an
effective contraceptive since her last menses. Many clinicians prefer to
insert an IUD within seven days of the onset of menstruation because the
cervical opening is slightly dilated during this time, making insertion
easier and pregnancy very unlikely. Insertion during these days also is
likely to result in less discomfort, cramping, and spotting for the patient.
The Copper T 380A IUD may be inserted immediately after an uncomplicated
first-trimester miscarriage or an induced abortion. A provider must ensure
that time is available for counseling and appropriate STD screening.
Shelf life
The shelf life of the Copper T 380A IUD is seven years. If the date on the
individual IUD sterilized packaging has expired, the device and its inserter
should be discarded.
Continuation rates
Continuation rates of IUD use have been generally among the highest of all
reversible contraceptives. Combined data from the Population Council and
World Health Organization studies indicate that 77 percent of women
continued using the Copper T 380A for one year. Sixty percent of the women
continued for two years, and almost half for three years, with 29 percent
continuing for eight years.
Prevalence of Use
Worldwide, the IUD is the most widely used reversible contraceptive. IUD
use varies from country to country, reflecting differences in culture,
availability, and choice of contraceptives, attitudes and training of
providers, and fertility goals of women. In Scandinavia, 20 to 40 percent of
contraceptive users have IUDs, while about 60 million Chinese women use
IUDs.
Return of fertility
The contraceptive effect offered by the Copper T 380A IUD is reversed when
the device is removed. Conception rates following removal for planned
pregnancy are normal, with rates of successful planned pregnancy unaffected
by duration of IUD use.
Copper-bearing IUDs may show discoloration in their sterile packaging, but
this should not cause alarm. The copper tarnishes because air passes through
the sterile IUD package, causing an oxide or sulfide film to form on the
surface. IUD packaging has to be permeable to sterilize the devices. If the
package is not damaged, and the expiration date on the package has not
passed, the IUD will be sterile even if the copper on the device is
tarnished. Laboratory studies show the tarnishing does not affect the safety
or effectiveness of the IUD.
Failure Rate
Pregnancy with the copper T 380A in place occurs at rates of less than one
per 100 women per year. If a woman using an IUD becomes pregnanat, the IUD
should be removed immediately.

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Conventionally Cu Ts are wound using copper wire. The copper wire is
wound on the Cu T stem under specified tension to ensure correct and uniform
winding. In single copper winding system one end of the copper wire is led
through the hole in the Cu T stem and is bent downwards. The winding is then
done over this bent end to create as anchor for winding.
This anchoring of one end by winding wire over the other end represents a
critical step and any loss of anchoring can result in low-tension winding
and pitch variations. Any loosening of wire from this end can result in
complete unwinding of copper wire. This form has a region of overlap of the
wire spiral over a variable length of wire. The spiral gets angulated over
the straight wire length. During winding wire tension varies over in this
zone with differing wire stretch. As a consequence of the overlap and
varying tension this region is susceptible to enhanced corrosion and the
wire end can also protrude. This situation represents a potential danger to
the user.
SMB Corporation has overcome this major disadvantage by adopting a new form
of winding using Programmable Logic Controller Technology. The double
winding form intrinsically rules out the possibility of protrusion. In this
winding, the copper wire is pulled through the stem hole till the stem is
midway along the wire length. The winding is then done using two strands on
either side of stem hole. The double copper winding system does not have
overlap and does not form electrochemical cells. The corrosion effect from
the electrochemical action is much less.
Double copper winding system has a definite advantage over the single
winding system.
Advantages of Double Copper Winding are:
- No protrusion or loose end near the stem hole.
- Uniform wire tension throughout the winding length makes it more
elegant.
- Smooth and uniform winding over the stem.
- Winding is difficult to unwind.
- Less corrosion.
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