The letters IUD stand for “intrauterine device.” IUDs are small, “T-shaped” devices made of flexible plastic. A health care provider inserts an IUD into a woman’s uterus to prevent pregnancy.

There are two brands of IUD available in the United States:

  • ParaGard – IUD contains copper. It is effective for 12 years.
  • Mirena – IUD releases a small amount of progestin, a hormone. It is effective for five years.

Both the ParaGard and the Mirena IUDs work mainly by affecting the way sperm move so they can’t join with an egg. If sperm cannot join with an egg, pregnancy cannot happen.

For some women, Mirena may prevent the egg from leaving the ovary. Pregnancy cannot happen if there is no egg to join with sperm. Progestin also prevents pregnancy by thickening a woman’s cervical mucus. The mucus blocks sperm and keeps it from joining with an egg.

Effectiveness is an important and common concern when choosing a birth control method. IUDs are one of the most effective forms of birth control available. Less than 1 out of 100 women will get pregnant each year if they use the ParaGard or the Mirena IUD.

Keep in mind that the IUD doesn’t protect against sexually transmitted infections. Use a latex or female condom along with the IUD to reduce the risk of infection.

The ParaGard IUD can be used as emergency birth control, to prevent pregnancy after unprotected intercourse. It can reduce the risk of pregnancy by 99.9 percent if inserted within 120 hours (five days) after unprotected intercourse.

Most women can use either the ParaGard or the Mirena IUD safely. But all medications have some risks, so safety is a common concern when choosing a birth control method. Certain conditions increase the risk of side effects. Talk with your health care provider about your health and whether an IUD is likely to be safe for you. There are many other methods of birth control that may be safe for you if you cannot use an IUD.

You should not use an IUD if you

• have had a pelvic infection following either childbirth or an abortion in the past three months
• have or may have a sexually transmitted infection or other pelvic infection
• think you might be pregnant
• have cervical cancer that hasn’t been treated
• have cancer of the uterus
• have unexplained bleeding in your vagina
• have pelvic tuberculosis
• have a uterine perforation during IUD insertion

A health care provider may find that the unique size, shape, or condition of a woman’s uterus does not allow correct placement of an IUD. This is not common.

You should not use the ParaGard IUD if you

• have, or may have, an allergy to copper or have Wilson’s Disease — an inherited disease that blocks the body’s ability to get rid of copper

You should not use the Mirena IUD if you

• have severe liver disease
• have, or may have, breast cancer

If you have a condition that makes it unsafe to use an IUD, don’t worry. There are many other methods of birth control that may be safe for you. Read about other methods to find one that is right for you.


The ParaGard and the Mirena IUDs are two of the least expensive, longest lasting forms of birth control available to women today. There are many other benefits.

• IUDs may improve your sex life. There is nothing to put in place before intercourse to prevent pregnancy. Some women say that they feel free to be more spontaneous because they do not have to worry about becoming pregnant.

• The ParaGard IUD does not change a woman’s hormone levels.

• The Mirena IUD may reduce period cramps and make your period lighter. On average, menstrual flow is reduced by 90 percent. For some women, periods stop altogether.

• IUDs can be used during breastfeeding.

• The ability to become pregnant returns quickly once the IUD is removed.

Some women may worry that they are pregnant if they do not have a regular period. But the IUD is very effective. If you are concerned about a possible pregnancy, you can always take a pregnancy test.

Overall, most women who get an IUD are very satisfied with their choice.

It’s important to think about the possible side effects of using an IUD.

You may have

• mild to moderate pain when the IUD is put in
• cramping or backache for a few days
• spotting between periods in the first 3–6 months
• irregular periods in the first 3–6 months — with Mirena
• heavier periods and worse menstrual cramps — with ParaGard

Pain relievers can usually reduce bleeding, cramping, and other discomforts. If they are severe and do not seem to lessen, tell your health care provider.

Serious problems with the IUD are rare. There are three main things to watch out for when using an IUD:

• The IUD can sometimes slip out of the uterus. Sometimes it comes all the way out. Sometimes it only comes out a little. This is more likely to happen to women who are younger and who have never had a baby. If the IUD slips out of place, pregnancy can happen. If it comes out only part of the way, it has to be removed.
• In rare situations, a woman could develop an infection when using the IUD. This happens if bacteria get into the uterus when the IUD is inserted. Most infections develop within three weeks of having the IUD inserted. If the infection is not treated, it can affect a woman’s ability to become pregnant in the future.
• In very rare situations, when the IUD is inserted, it can push through the wall of the uterus. This might sound painful, but it usually isn’t. Usually, when this happens, the health care provider will notice it and it can be fixed right away. But if not, the IUD can move around and harm other parts of the body. When this happens, surgery may be needed to remove the IUD.

Most often, if complications happen, they are easy to treat with medicine or other treatments.

It’s important to pay attention to any symptoms you might have after starting the IUD. Tell your health care provider immediately if you

• find the length of the string ends to be shorter or longer than they were at first, when you feel for them with your fingers
• are not able to feel the string ends when you check
• feel the hard plastic bottom of the “T” part of the IUD against the cervix, when you check
• think you might be pregnant
• have periods that are much heavier than normal or last much longer than normal
• have severe abdominal cramping, pain, or tenderness in the abdomen
• have pain or bleeding during sex
• have unexplained fever and/or chills
• have flu-like symptoms, such as muscle aches or tiredness
• have unusual vaginal discharge
• have a missed, late, or unusually light period
• have unexplained vaginal bleeding

IUDs and Pregnancy

The risk of pregnancy while using a ParaGard or Mirena IUD is very low. But if the IUD slips out of place, pregnancy can happen. If you become pregnant, have the IUD removed as soon as you find out that you are pregnant. If you are pregnant with an IUD in place, there is an increased risk of

• ectopic pregnancy
• dangerous pelvic infection
• miscarriage
• early labor and delivery

Even with the risks, some women may choose not to have the IUD removed during pregnancy. If you don’t want to have the IUD removed while you are pregnant, you need to work with your health care provider through your pregnancy.

Ectopic pregnancies are a serious concern. They can be life-threatening. Women who use IUDs are much less likely to have an ectopic pregnancy than women who are not using birth control. But if a woman does become pregnant while using an IUD, it is more likely to be ectopic than if she was not using the IUD.

Symptoms of an ectopic pregnancy include

• irregular vaginal bleeding
• pain in the abdomen or tip of the shoulder
• sudden weakness or fainting

If you have any of these symptoms while using an IUD, get medical care right away.

You can have sex as soon as you like after the IUD is inserted.

• The ParaGard IUD is effective immediately.

• The Mirena IUD is effective immediately if inserted within seven days after the start of your period. If you have Mirena inserted at any other time during your menstrual cycle, use another method of birth control like a condom, female condom, or spermicide if you have vaginal intercourse during the first week after insertion. Protection will begin after seven days.


To get an IUD, you need to visit a health care provider. Your health care provider will ask you some questions about your medical history and the way you live your life. It is important to be open about your sex life because the IUD may not be right for you. But don’t worry. There are many other birth control methods to choose from if you cannot use the IUD.

If an IUD seems to be a good choice for you, your health care provider will check your vagina and internal organs. You may be tested for sexually transmitted infections or for other infections to make sure it’s safe for you to get an IUD. If you have any kind of pelvic infection, you may need treatment before getting an IUD.

An IUD can be inserted at any time of the month. But it is usually more comfortable if you have it inserted in the middle of your menstrual cycle. That is when the cervix — the opening to the uterus — is the most open.

An IUD can be inserted after a pregnancy or abortion.

You can have an IUD inserted

• up to 48 hours after giving birth OR after waiting at least four weeks after giving birth. Women who are breastfeeding should wait four weeks before having a Mirena IUD inserted.
• immediately after an aspiration abortion
• four weeks after a D&E abortion
• when the abortion is complete after taking the abortion pill. Your health care provider can help you decide when to get the IUD inserted.

A health care provider will insert the IUD. The IUD is inserted into the uterus through the cervix using special instruments.

It is common for women to feel some cramping when the IUD is inserted. Many women only feel mild discomfort. The cramps go away after you rest, or if you take some pain medication. Some health care providers suggest that women take pain medication before the IUD is inserted to lessen the cramps. Some health care providers inject a local anesthetic around the cervix to reduce discomfort.

When the IUD is inserted, some women may feel dizzy. Rarely, a woman might faint. You can ask someone to come with you when you get the IUD inserted so you don’t have to drive or go home alone. You should plan to rest at home until any discomfort goes away.

When the IUD is in place, a string will hang down into the vagina. It will be about one to two inches long.

You should have a checkup after your first period. Don’t wait longer than three months after you get your IUD to make sure it is still in place. Women using an IUD should have regular checkups to make sure everything is all right.

This can be done at the same time as your periodic GYN exam. Remember when you have your IUD inserted. That way, if you see other health care providers, you can tell them when it needs to be replaced. The ParaGard IUD should be replaced after 12 years. The Mirena IUD should be replaced after five years.

If an IUD is going to slip out of place, it will most likely happen in the first few months of use. But it may occur later. The IUD is most likely to slip out of place during your period. Check your pads, tampons, or cups to see if the IUD has fallen out. If it has, you must check with your health care provider. Until then, use another form of birth control such as latex or female condoms.

Between your periods, you can check for the string ends. It is especially important to check every few days for the first few months.

To check for the string ends …

• Wash your hands. Then either sit or squat down.

• Put your index or middle finger up into your vagina until you touch the cervix. Your cervix will feel firm and somewhat rubbery, much like the tip of your nose.

• Feel for the string ends that should be coming through. If you find them, it means that the IUD is in place and working. However, if the string ends feel longer or shorter than before, or if you feel the hard part of the IUD against your cervix, it may be that the IUD has moved and needs to be put back in place by your health care provider. You should not attempt to put the IUD back in place yourself. Be sure to use another form of birth control until it is put back in place.

• Do not pull on the string ends. Pulling might make the IUD move out of place or even come out.

Having an IUD removed or replaced is usually simple. Your health care provider will do it for you. Women should never try to remove IUDs themselves or ask nonprofessionals to do it for them. Serious damage could result.

In rare cases, IUDs cannot be easily pulled free. In these cases, the cervix may have to be dilated and a surgical tool may be used to free the IUD. In very rare cases, surgery becomes necessary.

Do you have questions? Would like to schedule an appointment with the top obgyn doctor in Downtown, Brooklyn, please contact our Brooklyn Heights office.

Dr. Amir Marashi, MD
Brooklyn GYN Place
142 Joralemon Street, Suite 4CF
Brooklyn, NY 11201
(Brooklyn Heights)


The information provided on this site is intended to educate the reader about certain medical conditions and certain possible treatment. It is not a substitute for examination, diagnosis, and medical care provided by a licensed and qualified health care professional. If you believe you, or someone you know suffers from the conditions described herein, please see your health care provider immediately. Do not attempt to treat yourself or anyone else without proper medical supervision.
  • Our office has a 24/7 answering service to address any emergencies.