What Is an IUD?

• An IUD, or intrauterine device, is a small, T-shaped piece of material that is inserted into a female's uterus by a qualified practitioner that prevents pregnancy for an extended period of time-- usually up to five years. It can, however, be removed by the doctor if the woman wishes to become pregnant before the five years are up.
  
  

What Types of IUD's Are There?

• In the United States, there are two types of medical IUDs available. One type is made of plastic and contains a low-dose of hormones similar to those used in birth control pills, while the other is made of copper and does not release hormones.
  
  Both types of IUD must be inserted by a medical doctor or practitioner and are available by prescription only. During insertion, the device is flattened into a special instrument that is used to penetrate the cervix, or opening to the uterus. Once inside, the doctor can release a hinge that allows the IUD to take on its T-shape.
  
  

Plastic, Hormone-Releasing IUDs

• Plastic, hormone-releasing IUDs, such as the name-brand Mirena, are small plastic devices that contain hormones like the ones found in birth control pills.
  
  This type of IUD works in two ways--first, by releasing hormones that prevent ovulation, like other forms of hormonal birth control. The T-shape of the device also can prevent sperm from entering the Fallopian tubes, where conception typically occurs.
  
  As with all IUDs, this type is inserted by a doctor or family-planning practitioner. It is usually inserted during a woman's period because this makes insertion easier due to the fact that the cervix is slightly opened during menses.
  
  

Copper IUDs

• Copper IUDs, which are similar in structure to plastic, hormone-containing IUDs, are made solely of copper and prevent pregnancy using a different mechanism.
  
  The brand name of the copper IUD in the United States is ParaGard . ParaGard works by utilizing copper, which interferes with the thickening of the endometrial tissue in the uterus, to prevent pregnancy. Like the plastic IUD, it also prevents sperm from entering the Fallopian tubes.
  
  

Other Considerations

• Both forms of IUD are 99% effective at preventing pregnancy.
  
  A higher risk of spotting, heavier-than-usual periods and increased menstrual cramping are common with IUD usage.
  
  For hormone-containing IUDs, there is an increased risk of blood clots, stroke and heart attack, as there is with any form of hormonal contraception, including the Pill. If you smoke heavily or are over 35, this risk is increased. It is strongly advised that you do not smoke while on hormonal birth control of any kind.
  
  In the rare instance that you are to become pregnant while using an IUD, consult a medical professional immediately. Having an IUD implanted increases the likelihood of tubal pregnancy, so it is imperative that you receive medical attention as soon as possible.
  
  For help in determining which is right for you, consult with your physician or family planning clinic.