Clinical studies have found that the hormonal IUD is a consistently effective treatment for heavy menstrual bleeding up to 5 years. It may be effective for longer than five years, but this effect is likely to be less consistent.

Hormonal IUDs inhibit the hormone that triggers the growth and thickening of the uterine lining (the endometrium) over the course of the menstrual cycle. As a result, the uterine lining becomes thinner. When a hormonal IUD user has their monthly period, there is very minimal blood and tissue to be released. They may see only a small amount of bleeding during their period or their monthly bleeding may be paused while they use the method.

While some users experience immediate reduction in bleeding, most experience an adjustment period as their body gets used to the method and absorbs the hormone into the uterus. During this adjustment period, which typically lasts 3-6 months after insertion, bleeding may be more frequent, irregular, painful, or heavier. While every body is different and reactions to the method are highly individual, most users will begin to see a reduction in these effects after 3-6 months and almost all will experience reduced or paused bleeding shortly thereafter.

No, blood is not accumulating in the body. Because the hormonal IUD limits the growth of the uterine lining over the course of the menstrual cycle, there is not an accumulation of blood and tissue in the uterus during method use.

Yes, paused monthly periods alone due to the reduction in blood and tissue in the uterus are not dangerous and do not impact future fertility after stopping use of the hormonal IUD. However, unexplained amenorrhea when not using a contraceptive method associated with that effect may be linked to health concerns. If a person is concerned about paused monthly periods, whether or not they’re using a contraceptive method, they should speak to their family planning provider.

Heavy bleeding or severe pain within a few days of method insertion, sudden changes in bleeding after routine bleeding patterns have been established, bleeding that lasts much longer than their typical monthly bleeding, unusual or foul-smelling vaginal discharge, fever, or chills are all indicators of a potential complication. If a client experiences any side effects or changes to bleeding that they’re concerned about, regardless of severity, they should see a provider trained to offer the hormonal IUD to discuss what they’re experiencing and learn about their treatment options if needed.

Typically, no. Paused monthly bleeding is a common side effect of hormonal IUD use, experienced by around 20% of users in the first year of use and 40% of users by the end of the second year. However, hormonal IUD users should be given a pregnancy test if they are concerned about a potential pregnancy and should be counseled on possible early signs of pregnancy to help with self-identification.

Most hormonal IUD users will still experience a normal menstrual cycle and ovulation while using the method, particularly over time. Clinical evaluation has determined that within the first year of use, 45% of menstrual cycles in users are ovulatory, and after four years of use, 75% of cycles are ovulatory. The hormonal IUD’s effect is primarily local, meaning it’s not capable of consistently effecting processes that occur in multiple systems in the body simultaneously, like the menstrual cycle and ovulation.

There is not yet a reliable method of predicting what bleeding changes individual clients may experience when using the hormonal IUD. Bodies uniquely react to hormonal methods and to the physical presence of the IUD in the uterus based on a combination of genetics, physical characteristics, diet and exercise, lived experiences, and brain chemistry. Some preliminary research has identified genetic markers that may make a person more likely to experience irregular or longer bleeding while using the hormonal IUD, but this research is not yet able to be applied in a clinical setting. It’s essential that each client receive comprehensive counseling on possible bleeding changes and other side effects, and that providers are receptive and ready to respond to client questions and concerns.