An IUD is a form of long-term, reversible contraception that is inserted and remains inside your uterus while preventing fertilization. The IUD is a small, T-shaped device about the size of a large paperclip. There are two types of IUDs currently on the market: hormonal and copper. Both must be inserted by a health care provider, and both are highly effective at preventing pregnancy for several years.
The hormonal IUD is better known by its brand names Mirena, Skyla and Kyleena. Slowly and over a long period of time, hormonal IUDs release levonorgestrel, a hormone related to progestin. The hormone thickens the cervical mucus, which stops sperm from entering the uterus. It also makes it difficult for a fertilized egg to implant in the endometrium.
Mirena, Skyla and Kyleena can all prevent pregnancy. Mirena can remain in your uterus for up to 5 years, whereas Skyla can only be used up to 3 years but it is smaller in size and releases less hormones. Kyleena (which was FDA-approved in 2016) offers the best of both worlds, smaller in size, less hormones and approved for up to 5 years.
In most patients, hormonal IUDs can ease cramping and decrease menstrual bleeding.
Paraguard is the most common brand of copper IUD. Wound around the stem of the IUD is a thin wire made of copper, a substance which makes the uterine environment toxic to sperm.
Although the copper IUD is only a slightly less effective contraceptive than Mirena, it can remain in place for up to 10 years.
A copper IUD can be used as emergency contraception in some cases. If you’ve had unprotected sex in the past 72 hours and wish to continue using an IUD after insertion, the copper IUD can prevent a possible pregnancy. However, this option is more expensive than the oral Plan B pill.
You can make an insertion appointment with your OB-GYN at any time, as long as your pelvis is generally healthy and you aren’t pregnant. Before insertion, your doctor may want to have you screened for STIs.
On the day of insertion, your doctor can prescribe medication to soften the cervix, or administer a local anesthetic to help with the discomfort. The insertion can also be performed without drugs if you prefer.
The procedure is no more invasive than a Pap smear, and takes less than 5 minutes. Some patients find the insertion painful, while others report that it feels similar to a menstrual cramp. The process tends to be easier for patients who have given birth vaginally in the past.
When your IUD is in place, you should be able to feel a small string hanging from your cervix. Your doctor can show you how to locate it. The string will not be visible from the outside and won’t interfere with sex. If the string is a little too long, your doctor can clip it for you.
After IUD Insertion
It’s a good idea to have a trusted friend or family member drive you home after your procedure. Most patients will experience some cramping and bleeding for a couple days. Avoid inserting anything into your vagina during this time, including tampons, and avoid penetrative sex.
You may take ibuprofen and use a heating pad to manage the pain during the first day. You may want to take the day off work to rest. You should be able to return to work the next day.
Your doctor may schedule another appointment with you 3-6 weeks after your insertion. She will check to make sure the IUD is still in place and can address any questions or concerns you may have.
After your next few periods, you should check with your fingers to make sure you can feel the string. It’s very uncommon for a patient’s uterus to expel the IUD spontaneously, but it can happen. Insert your finger into your vagina and feel for the plastic string. It will feel a little like fishing line.
If you can’t feel it, call your doctor. It may have been expelled, or the string may have just wrapped itself around the cervix. If you’re not sure the IUD is in place, use another form of contraception until you can see your doctor.
Who is a Good Candidate for an IUD?
An IUD is a safe, effective, convenient, and easily-reversible form of birth control. An IUD may be right for you if you:
- Are in a low-risk category for STIs and pelvic inflammatory disease.
- Have only one sex partner who is infection-free.
- Use another form of contraception to guard against STIs, such as condoms.
- Cannot or do not want to use hormonal birth control methods.
- Find it difficult to take oral contraceptives daily.
- Are breastfeeding.
- Have a history of irregular bleeding, painful periods, or endometriosis.
Benefits of IUD
- Extremely effective at preventing pregnancy. Less than 1% of women will become pregnant in the first year after insertion. A pregnancy is most likely to occur if the IUD has been expelled from the uterus without the patient noticing.
- Cost-effective over time. IUDs are usually covered by insurance plans, and provide contraception for several years after insertion.
- Easily reversible. If you wish to become pregnant, you can have your IUD removed by your doctor at anytime.
- Easy to use. Aside from checking that the IUD remains in place every month or so, you can forget it’s there. You do not need to interrupt sex in order to protect against pregnancy.
- Significantly reduces menstrual bleeding and cramps after 3-4 months (Mirena). In some cases, periods may stop completely. This will not affect future fertility should you decide to remove the IUD to become pregnant.
- May reduce the risk of endometrial hyperplasia, endometrial cancer, and ectopic pregnancy.
- May treat the symptoms of endometriosis.
- Will not cause weight gain.
Risks of IUD
- May increase cramps and menstrual bleeding (Paraguard).
- Increased risk of benign (noncancerous) ovarian cysts (Mirena). These tend to resolve on their own.
- Side effects such as mood swings, acne, headaches, and tenderness in the breasts (Mirena). These side effects tend to disappear after 3-4 months.
- No protection against STIs.
- Spotting. Some patients may experience light spotting between their periods.
- Expulsion from the uterus. In 2-10% of cases, the IUD may be spontaneously expelled from the uterus during the first year. It’s more common in the early months after insertion, if the woman has never been pregnant, or if the IUD was inserted immediately after giving birth. The IUD can be re-inserted, but another form of contraception must be used in the meantime.
- Uterine perforation. In one out of 1,000 patients, the device may perforate (puncture) the uterine wall. This is a serious complication and will require immediate medical intervention.
Does IUD Increase the Risk of Pelvic Inflammatory Disease?
No. This rumor began with a kernel of truth. If you have a genital infection when your IUD is inserted, there is a possibility that the infection can be carried to your uterus and fallopian tubes. To reduce this risk, your doctor will have you tested for STIs and treat any infection prior to IUD insertion.
When to Call Your Doctor
Call your doctor right away if you:
- Experience heavy vaginal bleeding, such as if you have soaked through a pad or tampon each hour for more than 2 hours.
- Experience severe pelvic pain.
- Have a fever or chills.
- Notice foul-smelling vaginal discharge.
- Cannot locate the string of your IUD, or if the string feels longer or shorter than usual.
- Might be pregnant.
- Might have contracted an STI.
What if I Become Pregnant with my IUD?
If your IUD becomes dislodged from your uterus, there is a chance you could become pregnant. In this unlikely event, your doctor will recommend that you have the IUD removed, as it may cause miscarriage, ectopic pregnancy, or preterm delivery. The IUD will not increase the risk of birth defects.