Fact Sheet
Hormonal IUD
A small T-shaped piece of plastic containing progestin that can stay in the uterus for up to 5 years.
What is the hormonal IUD?
- The hormonal IUD (intra-uterine contraception device) is a small, T-shaped piece of plastic with a band containing one hormone (progestin) that a clinician inserts into your uterus*. It slowly releases a low dose of one hormone (progestin) over several years.
- The models available in Canada are called Mirena and Kyleena. Kyleena gives a slightly lower dose of hormones than the Mirena and is a little bit smaller.
How does the hormonal IUD prevent pregnancy?
- In order to get pregnant, sperm must enter your vagina*, swim up into your uterus and fertilize an egg that has been released from your ovaries during ovulation. Having an IUD in your uterus changes the chemistry of the uterus and makes it hard for sperm and eggs to survive and meet.
- The progestin thickens the mucus in your cervix (the opening to your uterus), which makes it harder for sperm to get into your uterus and fertilize an egg.
- It also thins the lining of your uterus (the endometrium). This makes it harder for a fertilized egg to implant in your uterus and become a pregnancy.
- For some people, the hormonal IUD may stop eggs from being released from your ovaries (ovulation).
- The Mirena can be used as emergency contraception to prevent pregnancy up to 5 days after sperm has entered your vagina. (This is an off-label use, and not all providers offer it.)
*We know that these aren’t the words everyone uses for their bodies (e.g. trans folks), and support you using the language that feels best for you.
How effective is the hormonal IUD?
- The hormonal IUD is 99.8% effective. This means that if 1,000 people had a hormonal IUD in place for one year, only 2 of them would get pregnant.
How do you use the hormonal IUD?
- A clinician inserts the IUD into your uterus.
- The hormonal IUD looks like a plastic T with strings attached at the bottom. The plastic part stays in your uterus, and the strings hang outside your cervix. The strings are short and will not hang outside your vagina. You can feel them if you put a finger into your vagina and touch your cervix, but the strings cannot usually be felt with a penis*. It is normal for the strings to move around a bit or seem to change length. If you are curious, you can check your strings by feeling for them with your finger(s).
- You can have a hormonal IUD removed by a clinician at any time or leave it in place up to 8 years (Mirena) or 5 years (Kyleena).
How to start using the hormonal IUD
- If you and your clinician decide that the hormonal IUD is right for you, they will write you a prescription. You can buy it at a pharmacy (approximately $375-$550) or at a sexual health clinic that sells IUDs (approx. $350-$400). PPT’s Health Services clinic inserts IUDs and sells the hormonal IUD for $360.25 (Kyleena) or $364.25 (Mirena).
- Hormonal IUDs may be covered by drug benefit plans (check with your provider). Hormonal IUDs are covered by OHIP+. If you can’t afford a hormonal IUD and don’t have any coverage for it, your clinician may be able to request a free one for you through the manufacturer’s compassionate program, or some sexual health clinics (including PPT) may be able to help with the cost.
- On the day of the insertion, your clinician may do a pelvic exam and test you for some sexually transmitted infections (STIs). They will also want to make sure you are not pregnant. There can be increased risks if you are pregnant when the IUD is inserted.
- It may be easier to get an IUD inserted while you are on your period, but this is not always necessary.
- Your clinician will measure your uterus with a thin rod called a sound and insert the IUD into your uterus using a thin (less than 5mm) applicator tube.
- During insertion, you will likely have strong cramping, more painful than normal period cramps. Your clinician may use a tool to hold your cervix steady that can feel like a sharp pinch. Talk with your clinician about pain management options. Some people take an over-the-counter painkiller before their insertion. Some clinicians offer local anesthetic (a numbing spray or injection to the cervix) for the insertion. A small number of clinics offer insertion with sedation.
- After insertion, you may feel some pain and cramping. This usually goes away within a few days. Your clinician will discuss ways to manage any discomfort you may have after the insertion.
- You will be protected from pregnancy 7 days after the insertion.
- It is recommended to avoid inserting anything into your vagina, including fingers, toys, penises, tampons, and menstrual cups for at least 48 hours after the insertion.
What are the side effects of the hormonal IUD?
- You may have spotting (a small amount of blood lighter than a period) or light bleeding frequently for the first 3-6 months.
- Your periods may be lighter, shorter, less crampy, or more irregular.
- After one year, 16-44% of people stop having periods while the IUD is in place. Mirena is more likely to stop your periods than Kyleena.
- Other side effects may include acne, headache, and sore breasts*.
- Talk to your clinician if you have a history of depression or if you are concerned about potential weight gain.
Advantages of the hormonal IUD
- Your chances of getting pregnant are extremely low.
- It can be used for up to 8 years (Mirena) or 5 years (Kyleena).
- You don’t have to do anything just before or after you have sex.
- It is a relatively “hands off” method. You only need to have a clinician check for your strings when you get a routine pelvic exam to make sure the IUD is in place.
- It may make your period lighter and less crampy. After one year, 16-44% of people stop having periods while the IUD is in place.
- You can use it if you can’t use birth control with estrogen.
- It doesn’t affect your ability to get pregnant after you stop using it.
- You don’t have to rely on your partner(s) to use it.
- If you want to keep your birth control use private, there is no packaging to be found.
- Over the course of 5-8 years, the monthly cost of the IUD works out to be cheaper than other hormonal options like the pill or ring.
- The hormonal IUD releases a very small amount of hormone compared to other hormonal methods like the pill, patch, or ring.
Disadvantages of the hormonal IUD
- A clinician must insert and remove the IUD.
- Insertion is usually uncomfortable or painful.
- There is small chance (2-10%) your body could expel (push out) your IUD, most commonly in the first 6 weeks after insertion. If it expels within the first 6 weeks, your clinician can apply to the manufacturer for a free replacement. If it expels after the first 6 weeks and you want another IUD, you will have to pay for a new one – the old expelled IUD cannot be reinserted.
- There is a very small chance that the IUD could break through the wall of your uterus while it is being put in (fewer than 1 in 1000 insertions). Your uterus should heal if this happens.
- If you have an STI or other infection when you get an IUD or get one within the first 3 weeks of having an IUD, you have a slightly higher risk of developing pelvic inflammatory disease (PID). PID can be painful and can lead to infertility. The risk of PID after 3 weeks is not significantly higher than for people without IUDs.
- IUDs make any pregnancy very unlikely but with IUDs in place a higher proportion of the pregnancies that do happen are ectopic (they happen outside of the uterus). Overall, the rate of ectopic pregnancy is lower with an IUD than in the general population.
- You may have side effects.
- Some people may not be comfortable using a method that can take their period away.
- It doesn’t protect you from STIs.