Different IUD options can include copper and hormonal options. How long they work for and potential side effects can vary.

Although more than 25 percent of women rely on the birth control pill, some women don’t want to take the pill or have difficulty remembering to take it.

For many women, intrauterine devices (IUDs) serve as a welcome alternative to the birth control pill. An IUD is a T-shaped device that your doctor inserts into your uterus.

Depending on the type that you get, the IUD can prevent pregnancy for up to 10 years. IUDs can cost up to $1,000 up front depending on your insurance, which is more than the cost of birth control pills. However, you won’t have to think about the IUD once it’s in place.

IUDs are either copper or hormonal. ParaGard is an example of a copper IUD. Mirena, Skyla, Liletta are examples of hormonal IUDs. Here’s a look at hormonal and copper IUDs, how they work, and their potential side effects.

The three brands of hormonal IUDs available are Liletta, Mirena, and Skyla.

Once placed in the uterus, this type of IUD slowly releases small amounts of the hormone progestin to stop sperm from reaching the egg. Similar to hormonal birth control pills, hormonal IUDs can also prevent ovulation, or the release of an egg from the ovary. The hormones also thicken the cervical mucus to prevent sperm from swimming to the egg and thin the uterine lining to stop a fertilized egg from implanting.

In addition to preventing pregnancies, hormonal IUDs will lighten your periods and reduce cramps. Mirena and Liletta may get rid of your periods entirely. For the first three to six months after the IUD is inserted, your periods will likely be unpredictable.

Skyla and Liletta continue to work for up to three years. Mirena can prevent pregnancy for up to five years.

Hormonal IUDs can cause side effects similar to those of birth control pills, including:

  • breast soreness
  • breast tenderness
  • headaches
  • nausea
  • mood changes
  • weight gain
  • acne

ParaGard is an IUD that’s wrapped in copper wire. Once it’s in place, it works for up to 10 years.

ParaGard can also be used as a form of emergency birth control after you’ve had unprotected sex. If you’ve the IUD inserted within five days after having unprotected sex or experiencing contraceptive failure, it’s almost 100 percent effective in preventing a pregnancy.

You may experience heavier bleeding and more cramps during your periods when using ParaGard. Your periods should lighten after a few months of having the IUD.

Other side effects of ParaGard may include:

  • anemia
  • backaches
  • spotting between periods
  • vaginal discharge
  • pain during sex

Both copper and hormonal IUDs prevent pregnancy by affecting sperm movement. They stop sperm from meeting up with the egg.

The two types of IUD are about equally effective. Fewer than one out of every 100 women using either the copper or hormonal IUD will get pregnant in any given year.

Read more: Mirena vs. ParaGard vs. Skyla: Choosing the Right IUD »

Although each type of IUD protects against pregnancy for a different amount of time, they can each be removed at any time. Removal is always an option if you decide you want to get pregnant or are unhappy with the side effects.

The main difference between the two types of IUDs is that one type releases hormones and the other doesn’t. In addition to blocking sperm from reaching the egg, hormonal IUDs thicken cervical mucus, thin the uterine lining, and prevent ovulation.

Each type of IUD works for a different length of time. Skyla and Liletta work for three years, Mirena for five years, and ParaGard for up to 10 years.

ParaGard starts to work immediately after you have it inserted. It can take Mirena, Skyla, and Liletta a week to start working. You may need to use a backup birth control method during that time.

Hormonal IUDs should make your periods lighter and accompanied by fewer cramps. With the copper IUD, your periods may get temporarily heavier and you might experience more cramps than usual.

The IUD is generally safe, but it isn’t right for every woman. You shouldn’t get any type of IUD if you:

  • recently had a sexually transmitted infection or pelvic inflammatory disease
  • have cervical, ovarian, or endometrial cancer
  • have unexplained vaginal bleeding
  • have a problem with your uterus, such as fibroids, that would make the IUD hard to insert
  • have liver disease
  • are pregnant

ParaGard can increase your risk of pelvic inflammatory disease (PID).

Read more: IUDs and Infection: Know the Facts »

Because ParaGard contains copper, you shouldn’t use this IUD if you have a copper allergy. You should also avoid this birth control method if you have Wilson’s disease, a condition that causes copper to build up in your body.

Your doctor will insert the IUD into your uterus through your vagina and cervix using an applicator. The whole process takes about 10 minutes. During the procedure, you may experience cramping or dizziness.

The IUD has a string attached to it. This string helps you check to make sure the IUD is still in place. It also helps your doctor remove the IUD.

After the IUD is inserted, you may have temporary side effects such as:

  • menstrual-like cramps
  • a backache
  • heavier than normal periods
  • spotting between periods
  • irregular periods

More serious side effects are rare, but can include:

  • PID
  • shifting of the IUD
  • expulsion of the IUD
  • perforation of the wall of the uterus

Before deciding on an IUD or any other birth control method, you should talk about the benefits and risks with your doctor. It’s important to consider the cost, convenience, and side effects when making your choice.

If you try this method and decide that it’s not for you, you can meet with your doctor to have your IUD removed. There are countless birth control options available, and your doctor can help you figure out which method is best for you.