What is an IUD (Intrauterine Device)?

The IUD is a small device that is inserted and left inside the uterus for prevention of pregnancy. IUDs work primarily by preventing fertilization of the egg by the sperm. An IUD provides a highly effective, long-acting method of birth control, without the need to take a pill every day or to use a method right before sex. IUDs are over 99% effective, meaning that fewer than 1 woman out of every 100 women who use the IUD for one year will get pregnant. In general, the longer a woman wears an IUD, the lower the chances of pregnancy. IUDs are as effective at preventing pregnancy as sterilization and begin to work immediately after insertion. Women are able to get pregnant right after an IUD is removed, although it is recommended to wait several months before trying to conceive.

CHCW is currently using two IUDs. The first is called Mirena and provides birth control for 5 years. The Mirena contains progesterone, which is a hormone. It is released locally into the uterine lining (there is very little absorption into the body). It is common to have light, irregular bleeding or spotting for several months after a Mirena is inserted. Eventually, however, this type of bleeding should stop and periods will either be light or may stop entirely. This improvement in menstrual periods is one of the real advantages of the Mirena IUD and is why it can be very useful for women who typically have heavy flow.

The second IUD is the Paragard. It is a copper IUD and provides birth control for ten years. There are no hormones in the Paragard so periods should continue regularly, but they can potentially be heavier and crampier. It is not certain how IUDs prevent pregnancy. Most likely they interfere with sperm transport through the uterus and they create an environment within the uterus that is not hospitable for a pregnancy.

How Is the IUD Inserted?

An IUD insertion is performed in the office and only takes a few minutes. While they can be placed at any time during the menstrual cycle it is preferred that they be placed during a period. The reason for this timing is two-fold. First, at the time of a period pregnancy is unlikely. Secondly, during a period the cervix is usually slightly dilated which makes insertion easier. Menstrual-type cramps can be felt during and shortly after the insertion. It is very helpful to take Ibuprofen about an hour beforehand.

After the pelvic exam, your CHCW physician will determine the size and position of your uterus by using a procedure known as “sounding.” He or she will open your vagina with an instrument called a speculum, and wash your cervix with a disinfectant. A long clamp, called a tenaculum, grasps your cervix and helps steady your uterus, minimizing the likelihood of perforation. Your doctor will push a uterine sound, a blunt rod-shaped instrument, through your cervical canal and into the uterus to determine whether your uterus is big enough to accommodate an IUD (it should be at least 2¼ inches) and if so, how deep he or she will need to insert the IUD to reach the top of the uterus (the fundus).

Your doctor then folds down the arms of the T-shaped IUD device and loads it into a long tube. The tube is then inserted into the uterus and the IUD is released by slowly and gently withdrawing the tube. This part of the procedure may cause cramping due to uterine contractions.

Who Is Best Suited for an IUD?

IUDs are best suited for women in a mutually monogamous relationship who have no history of ectopic pregnancies or pelvic infections. IUDs provide no protection against sexually transmitted diseases (STDs). If a woman contracts a STD with an IUD in place, she is at risk for getting a serious pelvic infection which can also cause infertility.

Women who have had at least one child often do better with IUDs because the uterus is larger after pregnancy and childbirth.

Side Effects

If any of the following problems occur, call CHCW and state that you are an IUD user:

  • Missed period.
  • Abnormal vaginal discharge or bleeding.
  • Pain with intercourse or pelvic pain.
  • If you are exposed to a sexually transmitted infection.
  • You are unable to locate your IUD string or the string has become much longer.
  • Your IUD partially or completely expels (comes out of the uterus).

For more information about IUDs, please ask your CHCW physician.