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Home > Wellness > Health Library > Intrauterine Device (IUD) for Birth Control
An IUD is a small, T-shaped plastic device that
is wrapped in copper or contains hormones. The IUD is inserted into your
uterus by your doctor. A plastic string tied to the
end of the IUD hangs down through the
cervix into the
vagina. You can check that the IUD is in place by
feeling for this string. The string is also used by your doctor to remove the
Both types of IUD prevent
fertilization of the egg by damaging or killing sperm. The IUD also affects the
uterine lining (where a fertilized egg would implant and grow).
You can have an IUD inserted at any
time, as long as you are not pregnant and you don't have a pelvic infection. An IUD is inserted into your uterus by
your doctor. The
insertion procedure takes only a few minutes and can
be done in a doctor's office. Sometimes a
local anesthetic is injected into the area around the
cervix, but this is not always needed.
IUD insertion is easiest in
women who have had a vaginal childbirth in the past.
may have you feel for the IUD string right after insertion, to be sure you know
what it feels like.
You may want to have someone drive you
home after the insertion procedure. You may experience some mild cramping and
light bleeding (spotting) for 1 or 2 days.
Your doctor may want to see you 4 to 6
weeks after the IUD insertion, to make sure it is in place.
sure to check the string of your IUD after every period. To do this, insert a
finger into your vagina and feel for the cervix, which is at the top of the
vagina and feels harder than the rest of your vagina (some women say it feels
like the tip of your nose). You should be able to feel the thin, plastic string
coming out of the opening of your cervix. It may coil around the cervix, which
can make it difficult to find. Call your doctor if you cannot feel the string
or the rigid end of the IUD.
If you cannot feel the string, it
doesn't necessarily mean that the IUD has been expelled. Sometimes the string
is just difficult to feel or has been pulled up into the cervical canal (which
will not harm you). An exam and sometimes an
ultrasound will show whether the IUD is still in
place. Use another form of birth control until your doctor makes sure that the
IUD is still in place.
If you have no problems, check the string
after each period and return to your doctor once a year for a checkup.
You may be a good candidate for an IUD
The copper IUD is recommended for
emergency contraception if you have had unprotected
sex in the past few days and need to avoid pregnancy and
you plan to continue using the IUD for birth control. As a short-term type of
emergency contraception, the copper IUD is more expensive than emergency
contraception with hormone pills.
The IUD is a highly effective method
of birth control.1
Advantages of IUDs include cost-effectiveness over time,
ease of use, lower risk of
ectopic pregnancy, and no interruption of foreplay or
the hormonal IUD:
Risks of using an intrauterine device (IUD)
Disadvantages of IUDs include the high cost of insertion,
no protection against STIs, and the need to be removed by a doctor.
The hormonal IUD may cause
noncancerous (benign) growths called
ovarian cysts, which usually go away on their
The hormonal IUD can cause hormonal side effects similar to those
caused by oral contraceptives, such as breast tenderness, mood swings,
headaches, and acne. This is rare. When side effects do happen, they usually go
away after the first few months.
Pregnancy with an IUD
If you become pregnant with an IUD in place, your doctor will recommend
that the IUD be removed. This is because the IUD can cause
preterm birth (the IUD will not cause birth defects).
When using an IUD, be
aware of warning signs of a more serious problem related to the IUD.
Call your doctor now or seek immediate medical care if:
Watch closely for changes in your health, and be sure to contact your doctor if:
The IUD is most likely to work well
for women who have been pregnant before. Women who have never been pregnant are
more likely to have pain and cramping after the IUD is inserted. They are also more likely to expel the IUD.
But they can still use the IUD.
Pelvic inflammatory disease (PID) concerns have been
linked to the IUD for years. But it is now known that the IUD itself does not
cause PID. Instead, if you have a genital infection when an IUD is inserted,
the infection can be carried into your uterus and fallopian tubes. If you are
at risk for a
sexually transmitted infection (STI), your doctor will
test you and treat you if necessary, before you get an IUD.
Intrauterine devices reduce the risk of all pregnancies, including
ectopic (tubal) pregnancy. But if a pregnancy does
occur while an IUD is in place, it is a little more likely that the pregnancy
will be ectopic. Ectopic pregnancies require medicine or surgery to remove the
pregnancy. Sometimes the fallopian tube on that side must be removed as
An IUD can be a
safe birth control choice for women who:4
Complete the special treatment information form (PDF)(What is a PDF document?) to help you understand this treatment.
Grimes DA (2007). Intrauterine devices (IUDs). In RA
Hatcher et al., eds., Contraceptive Technology, 19th
ed., pp. 117–143. New York: Ardent Media.
Trussell J (2007). Choosing a contraceptive:
Efficacy, safety, and personal considerations. In RA Hatcher et al., eds.,
Contraceptive Technology, 19th ed., pp. 19–47. New
York: Ardent Media.
Fritz MA, Speroff L (2011). Endometriosis. In Clinical Gynecologic Endocrinology and Infertility, 8th ed., pp. 1221–1248. Philadelphia: Lippincott Williams and Wilkins.
Speroff L, Darney PD (2005). Intrauterine
contraception. In Clinical Guide for Contraception, pp.
221–257. Philadelphia: Lippincott Williams and Wilkins.
May 3, 2012
Sarah Marshall, MD - Family Medicine & Femi Olatunbosun, MB, FRCSC - Obstetrics and Gynecology
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