Types of IUDs and Mechanism of Action

  • Joy FriedmanEmail author
  • Rubiliatu A. Oluronbi


There are currently 5 types of IUDs FDA approved for use in the United States, all of which are appropriate for use in adolescents and young adults. IUDs vary in composition and shape. Modern IUDs are categorized as copper-releasing, progestin-releasing, and inert or unmedicated. All types of IUDs have both primary and secondary mechanisms of action. The primary mechanism of action for all types IUDs is prevention of fertilization, though different types of IUDs do this differently. While these mechanisms are very effective at preventing fertilization in IUD users, unintended pregnancies including ectopics can rarely occur. This chapter will focus on the intrauterine contraceptives currently available in the United States as of 2018, and provide an example of how to discuss with adolescents, young adults, and their families.


Adolescent Young adult IUD Copper IUD Hormonal IUD Levonorgestrel IUD mechanism of action 



The American College of Obstetrics and Gynecology


Adolescent and Young Adult


Emergency Contraception


United States Federal Drug Administration


Intrauterine Device


Long-Acting Reversible Contraception




Unprotected Intercourse


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Department of PediatricsAlbert Einstein Medical CenterPhiladelphiaUSA
  2. 2.Department of Obstetrics and GynecologyAlbert Einstein Medical CenterPhiladelphiaUSA

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