In the week immediately following hormonal IUD insertion, cramping (similar to what someone would experience during their period) and mild-to-moderate abdominal pain is common. This typically resolves on its own within a week. If it doesn’t or if it becomes severe, the client should return to their provider. In the first 3-6 months of method use, irregular or longer menstrual bleeding may occur. This is normal and expected as the body adjusts to the hormonal IUD. Users may begin to see a reduction in menstrual blood loss during this time as well. Clients may also experience nausea, tender breasts, mood changes, headache, acne, or weight gain. These side effects are associated with the small amount of the hormone levonorgestrel entering the blood stream, and in almost all cases, they improve or go away in the first 6 months of method use as the hormone level in the blood decreases and the body adjusts. Clients should return to their provider to talk about any side effects that concern them, regardless of severity.

Over time, the most common side effect is significant reduction in menstrual bleeding (experienced by almost all users) or paused menstrual bleeding (experienced by 20-40% of users). While a hormonal IUD user is likely to never be aware of the effect, some users develop benign, painless ovarian cysts which resolve on their own. For almost all users, systemic side effects such as headache or nausea resolve or substantially improve over time, and clinical evidence suggests that most users do not experience any notable systemic effects after the first year of use. Importantly, for both short- and long-term effects, side effect presentation is extremely individual, and side effects being rare does not diminish the need to fully counsel clients on what they may experience during use of the method, though they should also receive information on the relative risk of each known effect. Clients should be empowered to return to their provider to talk about any changes or side effects that concern them, regardless of severity or known association with the hormonal IUD.

There is not yet a reliable method of predicting what side effects someone may experience while using the hormonal IUD. While previous experiences with hormonal contraceptives may provide some indication of how an individual might react to the hormonal IUD, the method’s unique attributes (very low daily dose, local effect, limited hormone release into the blood stream) prevent perfect comparison, even to other levonorgestrel-based contraceptives. Clinical evidence has suggested that younger, nulliparous users or users with smaller uterine cavities may experience slightly more abdominal pain and irregular bleeding during use than older users who have had children or those with larger uterine cavities, but this effect does not appear to be consistent. Providers should ensure each client receives comprehensive counselling on the method’s side effect profile, and clients should be encouraged to return to the clinic if they experience any side effects that concern them.

Systemic side effects, or side effects associated with multiple systems in the body, are caused by a drug’s active ingredient entering the blood stream and disseminating throughout the body. Only a small amount of the hormonal IUD’s active ingredient, levonorgestrel, enters the blood stream (as most is absorbed directly into the uterus and cervix), so its systemic side effects tend to be mild and often resolve within the first 6 months of use. These include headache, nausea, breast tenderness, mood changes, acne, and weight gain. Each hormonal IUD user will react to levonorgestrel differently, and so side effects vary from person to person. While many will experience few or no systemic side effects, a small number of users will experience more severe or longer-lasting effects. Users should talk to their provider if they experience any side effects that concern them.

Expulsion occurs in about 3-6% of hormonal IUD users during the first year after insertion and is most likely to occur in the first few months of use. Users who have recently given birth and/or are breastfeeding, adolescent users, and users with uterine distortion (typically due to fibroids) are at a slightly elevated risk of expulsion. Generally, expulsion is caused by improper placement of the hormonal IUD or improper insertion technique. The most common error is failing to properly sound the uterus to set the hormonal IUD inserter depth and, as a result, not fully advancing the IUD to the fundus. Clients should regularly check the strings of their IUD to confirm that it is still in place and should return to their provider if they cannot locate their strings or if they can feel the IUD in the vaginal canal or cervical canal. They should also return to their provider if they fully expel the IUD, meaning if the IUD has fully exited the body through the cervix and vagina.

Uterine perforation is a serious but extremely rare complication. In large population studies on the hormonal IUD, about 1-2 insertions out of 1000 resulted in uterine perforation, or about 0.2% of insertions. Risk of perforation is slightly elevated in post-partum and breastfeeding hormonal IUD users and younger users who have not given birth. Accurate uterine sounding and inserter depth-setting is essential to ensure that the hormonal IUD is advanced to the fundus without perforation. New providers should have supportive supervision to help ensure these steps are taken. Providers should be aware of the profile of patients more likely to experience perforation. The most consistent sign that perforation has taken place is severe abdominal pain in the week following insertion, though clients should be encouraged to return to their provider if they experience any effect they find concerning.

Approximately 0.005-0.01% of insertions result in the hormonal IUD fully exiting the uterus through the uterine wall, with the IUD adhering to the intestine (most commonly the rectum), the bladder, or abdominal wall. While this complication does significantly limit or eliminate the efficacy of the method, case studies suggest that many clients (as many as 1/3rd) experiencing migration are wholly asymptomatic and experience no increased pain or bleeding. Despite this, migration should be treated as a significant medical event warranting rapid intervention in all patients presenting with the concern. If an IUD cannot be visualized in the uterus by ultrasound, patients should be referred to higher-level medical facilities for full visualization of the abdomen and removal of the IUD through laparoscopy, cystoscopy, or laparotomy. There has never been a documented case of the hormonal IUD migrating outside of the abdomen (e.g., towards the heart or lungs) and no cases of adhesion to the liver, spleen, or kidneys. Migration is near-universally restricted to the lower abdomen, reproductive, and excretory systems. There are also no known deaths or cases of permanent disability associated with hormonal IUD migration.

No, the hormonal IUD does not increase the risk of acquiring HIV. The method has been evaluated in populations at risk of HIV and has not been associated with increased transmission. It does not, however, protect against HIV and individuals who desire HIV protection should use condoms and/or pre-exposure prophylaxis.

No, the hormonal IUD does not cause blood clotting and is safe to use by individuals at elevated risk of developing clots. The hormone in the hormonal IUD, levonorgestrel, is a synthetic form of the hormone progesterone, which has no association with blood clotting. This is different from contraceptives that contain the hormone estrogen, like the combination pill or many implants, which increase risk of blood clots.

Reporting serious complications is an important part of ensuring that medical products are safe to use. If a client experiences a serious complication or side effect, their provider should first determine the brand of hormonal IUD they were given and use the information below to report safety events directly to the product’s supplier. In addition to reporting to the product suppliers, providers should also notify their national drug regulatory agency of serious complications. This reporting process varies by country but information is typically available through the national drug regulator’s website. Providers should ensure that they are accurately reporting the specific hormonal IUD brand involved in the patient safety event. Mirena Bayer collects all safety information on their products, including Mirena, though SafeTrack. Providers should go to https://safetrack-public.bayer.com/ and complete the online tool in as much detail as possible. Providers can also report complications and side effects directly to the United States Food and Drug Administration, the method’s most stringent regulatory agency, at www.fda.gov/medwatch. Avibela Complications with Avibela, which is sold in the United States under the name Liletta, should be reported to Medicines360 via email at Liletta_Intake@abbvie.com and to the United States Food and Drug Administration at www.fda.gov/medwatch. Country-specific reporting emails can be found here: https://www.avibelapv.net.

The hormonal IUD is generally protective against reproductive cancers, lowering risk of both endometrial and cervical cancer. Risk of breast cancer during or after use of the hormonal IUD is complex. The hormonal IUD does not cause any increase in lifetime risk of developing breast cancer or dying from breast cancer. Use of the method may, however, accelerate growth of preexisting cancerous cells in the breast, leading to more diagnoses of breast cancer in older women with additional reproductive health concerns. In other words, a hormonal IUD cannot cause a patient to get breast cancer but may speed up the growth of cancerous cells in patients at higher risk due to age and comorbid conditions. Risk should be discussed with patients older than 40 seeking treatment for heavy menstrual bleeding.