Definition An intrauterine device (IUD) is a small, plastic device that contains copper or progesterone (a hormone). It is inserted within the cavity of the uterus by a doctor to prevent pregnancy.
What is the information for this topic? There are two ways an IUD prevents pregnancy. First, it creates a hostile environment for the sperm to travel through on the way to fertilise the egg. The IUD also prevents the fertilised egg from attaching to the walls of the uterus.
IUDs do not guarantee that pregnancy will not occur. The only method of contraception that guarantees no pregnancy is abstinence, which means no sexual intercourse. Many shapes and sizes of IUDs have been tried. Some work better than others and have different complications.
A trained professional inserts the IUD when the woman is having her menstrual period. This requires sterile technique and a pelvic examination. The examination will determine the size and position of a woman's uterus and will check for pelvic infection.
Not all women should use IUDs. The IUD is thought to be a good choice for a woman who:
has given birth.
has one steady partner.
has no history of a current or previous sexually transmitted diseases (STDs) or pelvic infection.
cannot use hormonal contraception due to side effects.
is at risk during pregnancy, due to a medical condition such as diabetes, and the risk is higher than the potential risks linked to use of an IUD.
IUDs should not be used with women who have:
a current known pregnancy.
abnormal vaginal bleeding.
current cervical, uterine or tubal infection.
past history of inflammation of the fallopian tubes or pelvic inflammatory disease (PID).
suspected gynaecologic cancer.
Another birth control method, other than an IUD, should be used by women who:
have multiple sexual partners.
have a high priority attached to future childbearing.
have a history of prior ectopic pregnancy.
moderate or severe menstrual cramps.
have a history of STDs.
have anatomic abnormalities of the uterus.
have heavy menstrual cycles with anaemia.
have abnormal heart valves.
have problems with previous IUD use.
have not had children
The potential risks and complications associated with the use of an IUD include:
unplanned pregnancy, with a failure rate of one percent (1%).
complications of insertion, including perforation of the uterus, fainting reaction from cervical dilation or anaesthetic allergy
pregnancy outside the uterus
septic abortion if the IUD is not removed after pregnancy is diagnosed
spontaneous ejection of the IUD
increased risk of pelvic inflammatory disease and salpingitis(an infection that has spread from the cervix up to the uterus, tubes and the abdominal cavity)
increased risk of infertility
Limiting the number of sexual partners can help prevent complications associated with IUD use. Practicing safer sex can help. Regular check ups with a doctor can help.
There is the potential for PID and infertility associated with insertion or very long-term IUD use.
The risk of HIV and STDs is not increased by IUDs. These are spread by sexual partners.
A woman with an IUD should have regular pelvic examinations. If any signs of potential infection or pregnancy arise, a doctor should be seen as soon as possible. Signs include:
fever.
abnormal vaginal discharge.
lower abdominal or pelvic pain.
breast tenderness.
nausea.
vomiting.
abnormal vaginal bleeding.
Author: Eva Martin, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request