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Ah yes, the big Kyleena vs. Mirena debate. Is Kyleena better than Mirena? How are they different? Does one hurt more than the other?

We answer all your Kyleena and Mirena Qs here so you can decide which hormonal intrauterine device (IUD) – if any – is right for you.

Kyleena Mirena
Drug
class
progestins progestins
Generic name Levonorgestrel 19.5 mg Levonorgestrel 52 mg
Benefits – over 99% effective
– low dose of hormones
– smaller size may mean easier insertion
– can be removed anytime
– over 99% effective
– treats heavy periods
– helps relieve cramps
– helps with endometriosis pain
– can be removed anytime
Side effects – irregular bleeding/spotting for 3-6 months
– 1 in 100 users stop menstruating after 1 year
– ovarian cysts
– irregular bleeding/spotting for 3-6 months
– 2 in 10 users stop menstruating after 1 year
– ovarian cysts
Duration Up to 5 years Up to 7 years
Average cost – $1049.24 without insurance
– $20 with Bayer Co-pay Savings Program
– Free with insurance
– $1049.24 without insurance
– $20 with Bayer Co-pay Savings Program
– Free with insurance

Kyleena is a hormonal IUD that prevents pregnancy for up to five years. The Kyleena website says it’s the smallest, lowest dose, five-year IUD. It contains 19.5 mg of the progestin levonorgestrel.

Kyleena works by gradually releasing progestin inside your uterus to prevent pregnancy. It acts almost like a bouncer for your uterus and helps keep sperm out and away from your eggs.

It’s believed it works a few ways to prevent pregnancy, including:

  • thickening your cervical mucus to block sperm from entering your uterus
  • inhibiting sperm movement to make it harder for sperm to reach and fertilize an egg
  • thinning the uterine lining so an egg is less likely to attach to the uterus

Kyleena pros:

  • Effectiveness. It’s one of the most effective birth control methods available.
  • Long lasting. Once inserted, it lasts for 5 years before it needs to be replaced.
  • Convenience. No pre-sex prep or reminders.
  • Smaller size. The smaller size may make insertion more comfortable.
  • Cost-effective. It may be a tad pricey upfront, but there are no other costs beyond that for 5 years.
  • Reversible. You can remove it any time and your fertility will return as soon as it’s removed.
  • Estrogen-free. It’s safe for people who can’t use birth control with estrogen.
  • Lighter periods. It can make periods lighter or stop them entirely for some.

Kyleena cons:

Mirena is another levonorgestrel-releasing IUD. Consider it one of Kyleena’s older siblings, because it’s bigger and has been around longer.

It contains 52 mg of levonorgestrel that’s released gradually to prevent pregnancy for up to 7 years.

It’s also FDA-approved for treating heavy periods for up to five years for people who choose an IUD as their method of contraception.

It works like Kyleena to prevent pregnancy by:

  • thickening your cervical mucus to block sperm from entering your uterus
  • inhibiting sperm movement to make it harder for sperm to reach and fertilize an egg
  • thinning the uterine lining so an egg is less likely to attach to the uterus

Mirena Pros

  • Effectiveness. It’s one of the most effective birth control methods available.
  • Long lasting. Once inserted, it lasts for 7 years before it needs to be replaced.
  • Convenience. No pre-sex prep or reminders.
  • Treats heavy periods. It’s an FDA-approved treatment for heavy menstrual bleeding.
  • Cost-effective. It may be a tad pricey upfront, but there are no other costs beyond that for 7 years.
  • Reversible. You can remove it any time and your fertility will return as soon as it’s removed.
  • Estrogen-free. It’s safe for people who can’t use birth control with estrogen.
  • Lighter periods. It can make periods lighter or stop them entirely for some.

IUDs are safe for most, but having certain conditions can increase the likelihood of side effects and complications.

IUDs aren’t recommended for people who:

Other possible risks to consider:

  • Infection. There’s a small risk of infection after insertion.
  • Expulsion. There’s a slight chance that your IUD could shift out of place.
  • Perforation. There’s a very low risk of perforation during insertion. We’re talking only a 1 to 2 in 1,000 chance.
  • Ectopic pregnancy. Getting an IUD won’t increase your risk of ectopic pregnancy if you decide to get pregnant. But if you get pregnant with an IUD in place, the risk of ectopic pregnancy is higher.

Side effects for Kyleena and Mirena usually go away after 3 to 6 months, once your body gets used to the hormones.

Side effects include:

Some side effects are typical

Side effects are possible while your body adjusts to the hormones and usually go away within 3 to 6 months.

Here are the answers to the most frequently asked Qs about Kyleena vs. Mirena.

How effective are the Kyleena and Mirena IUDs?

Very effective! Kyleena is over 99 percent effective for each year of use, and 98.6% effective over 5 years. Mirena is over 99 percent for 7 years.

Is the Kyleena or Mirena IUD better than the other?

Nope! Both are very effective at preventing pregnancy and have similar side effects. Mirena may be the better option if you’re also looking to treat heavy menstrual bleeding.

A healthcare professional can help you decide which is right for you.

How do the Kyleena and Mirena IUDs affect your period?

Both can cause irregular bleeding or spotting for the first year and both may make your periods lighter or stop entirely after a year of use.

Mirena thins the endometrial lining to a greater extent than Kyleena does. This is why 2 in 10 people using Mirena stop getting periods after a year compared to 1 in 100 people who use Kyleena.

Can the Kyleena and Mirena IUDs affect your weight?

It’s unlikely. There’s also no clear evidence linking hormonal contraceptives to weight gain. Weight gain also isn’t listed as a possible side effect of either IUD.

During clinical trials for Mirena, 6 percent of participants did report weight gain, but it’s unknown if it was actually caused by Mirena.

Can the Kyleena and Mirena IUDs affect your skin?

Yes, though Kyleena is more likely to affect your skin than Mirena. During clinical trials for Kyleena, 14.1 percent of participants developed acne and 1.8 percent developed greasy skin.

During clinical trials for Mirena, 6.8 percent of participants developed acne.

Are the Kyleena and Mirena IUDs the same size?

Nope! Kyleena is smaller than Mirena.

Kyleena measures 1.18 inches long and Mirena is 1.26 inches long. For some context, Kyleena is about a tad shorter than a paperclip. Mirena is shorter than a sugar packet.

There are a lot of similarities between Kyleena and Mirena, with the key differences between the two being size, duration, and the impact on heavy periods.

A healthcare professional can help you weigh your options and choose the right IUD for you. Remember that both of these can be removed anytime if you change your mind.

There are also plenty of other hormonal and hormone-free birth control methods to choose from if you do decide an IUD isn’t your jam.


Adrienne Santos-Longhurst is a Canada-based freelance writer and author who has written extensively on all things health and lifestyle for more than a decade. When she’s not holed-up in her writing shed researching an article or off interviewing health professionals, she can be found frolicking around her beach town with husband and dogs in tow or splashing about the lake trying to master the stand-up paddle board.