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- Abstinence
- Hormonal Contraception
- Barrier Methods
- Spermicides
- Withdrawal
- Natural Birth Control
- Intrauterine Device (IUD)
- Emergency Contraception
- Anticoncepción de Emergencia
-
Hitna Kontracepcija
- Tubal Ligation
What is an IUD?
The intrauterine device
(IUD) is a plastic device that is put into the uterus to prevent
pregnancy. There are two kinds used in the United States. One contains
copper wire and the other an artificial women's hormone (a progestin)
called levonorgestrel. The copper IUD may remain in the uterus for 10
years. The progestin IUD must be replaced after 5 years when much of the
hormone has been used. Both of the IUDs are "T" shaped.
How does it work?
There are several
theories on how IUDs work, but no one knows for sure. The IUD may
prevent fertilization (the joining of the egg and sperm) or it may
prevent the fertilized egg from implanting and growing on the wall of
the uterus. Here are some of the theories:
-
There may be
increased movement (muscle contractions) in the uterus and uterine
tubes and that may prevent fertilization or implantation.
-
There may be an
inflammatory response which prevents fertilization or implantation.
-
There may be
increased numbers of white blood cells from the imflammation (and
also from progestin in the progestin IUD) which destroy sperm and
the fertilized egg.
-
Progestin prevents
the growth of the lining of the uterus. It also causes cervical
mucus to be thicker which decreases sperm movement. It also contains
many white blood cells that destroy sperm.
-
Copper may decrease
sperm movement, ability to combine with the egg, and it also
destroys sperm.
-
There may be
increased production of prostaglandins that may interfere with
implantation.
How effective are
IUDs?
Effectiveness depends
on whether the woman checks for placement of the IUD string at the
cervical opening. Women who check the string every time before
intercourse will have higher effectiveness rates. Both theoretical and
use effectiveness rates of the two newer IUDs are greater than 99%.
IUDs are more likely to
be expelled from the uterus in the first 3 months after insertion.
How is the IUD
put into the uterus?
IUDs should be inserted
during a menstrual period. It is more comfortable because the cervix
(the neck of the uterus which is in the vagina) is softer and the
cervical os (its mouth or opening) is more open at that time. Also,
women are much less likely to be pregnant if they are having a period.
Most women feel some
cramping during insertion of the IUD and for several minutes after
insertion. Some report cramping for a day or two after and sometimes
during the first few menstrual periods.
Complications of
IUD use
-
Pelvic Inflammatory
Disease (PID)
PID is an infection of the uterus and sometimes of the tubes,
ovaries, and even the abdominal cavity. The risk of PID is much
lower if you and your partners have no other partners. If you
suspect that you may have a sexually transmitted infection (STI),
like gonorrhea or chlamydia, see a health care provider immediately
for treatment. It is important to be tested for STIs at least once a
year or whenever you suspect that you may have been exposed.
Symptoms of PID are a foul smelling discharge, pelvic pain or
tenderness, severe cramping, or a fever.
PID can cause scarring of the uterine tubes which can lead to the
inability to have children or an increased chance of having a
pregnancy in the tube. The tube ruptures around 8 to 12 weeks of a
pregnancy. This may result in severe bleeding which can cause death.
PID can cause chronic pelvic pain from scarring in the abdominal
cavity. The infection alone can also result in death if the woman is
not put on antibiotics soon enough.
-
Embedding or
perforation
The IUD can work its way partly through, or all the way through the
uterine wall. There may or may not be pain as this is happening.
Guard against this by checking for the string before intercourse, or
at least once a month.
The health care practitioner may injure the uterine wall during
insertion. The injury may go all the way into the abdominal cavity.
This is also called perforation. The perforation will heal, usually
needing no treatment.
-
Pregnancy with an
IUD in place
If a pregnancy does occur, there is a 50% chance that the woman will
have a miscarriage. She is at higher risk for infection with the IUD
in place. If the IUD is removed, there is a 25% chance of a
miscarriage.
Getting pregnant
after removal of an IUD
It is best to wait at
least 3 months after having an IUD removed to try to get pregnant. The
uterine lining needs time to return to normal functioning and it may
decrease the risk of an ectopic pregnancy.
Benefits of the
progestin IUD - Mirena
This IUD releases 20
micrograms of progestin a day. Studies have shown:
-
Lighter periods
with less cramping and bleeding - up to 88% less blood loss
-
Decreased bleeding
at menopause - may avoid hysterectomy
-
Decreased growth of
uterine lining with estrogen replacement therapy
-
Decreased pelvic
infections, therefore, fewer ectopic pregnancies
Side effects of
the progestin IUD - Mirena
-
no periods
-
acne
-
headaches
-
nausea
-
breast tenderness
Contraindications
to getting an IUD
You should not have an
IUD if you:
-
Are pregnant
-
Have PID or a
history of PID
-
Have endometriosis
-
Have been exposed
to or have gonorrhea or chlamydia
-
Have confirmed or
suspected cancer of the cervix or uterus
-
Undiagnosed
abnormal vaginal bleeding
-
Blood clot or
bleeding disorder
-
Acute liver disease
-
Have abnormalities
of the uterus such as those present from birth or possibly fibroids
Consider another birth
control method if:
-
You have more than
one partner or a partner with more than one partner
-
You are unable to
check the IUD string, especially if your partner is also unable to
check the string
IUDs Currently
Available (In the United States)
Copper T380A, brand
name: ParaGuard Intrauterine Copper Contraceptive
Manufacturer: Ortho-McNeil Pharmaceutical, Raritan, New Jersey
Progestin IUD, Brand
name: Mirena Legonorgestrel-Releasing Intrauterine System
Manufacturer: Berlex
Laboratories, Montville, New Jersey
BIBLIOGRAPHY
American Health
Consultants, Contraceptive Technology Update, Vol. 23, No. 4,
April 2002.
Boston Women's Health
Book Collective, Our Bodies, Ourselves, Simon & Schuster, 1998.
Hatcher, R., et al.,
Contraceptive Technology, 17th edition, Irvington Publishers, 1999.
Contraceptive
Technology Seminar, San Francisco, California, 2001.
Revised 12-2005 TM
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