How does an intrauterine device (IUD) work?

An intrauterine device (IUD) works by preventing fertilization. An IUD is  a T shaped device that is placed in the uterus to prevent pregancy.  There are two major types of IUDs -- hormonal IUDs and copper IUDs.  Hormonal IUDs release a hormone thought to stay primarily in the uterus and help prevent sperm from reaching the egg.  Copper IUDs are thought to prevent sperm from implanting in the egg.  IUDs are also thought to cause inflammation in the uterus, which helps prevent implanation.
Kevin W. Windom, MD
OBGYN (Obstetrics & Gynecology)
An IUD is a T-shaped device either made out of plastic or copper and it is placed inside the uterus to help prevent pregnancy. The copper IUD (ParaGard) uses copper to kill off sperm as well as decrease fallopian tube motility. The progesterone (Mirena) IUD is a plastic IUD that is implanted with progesterone and this IUD causes an increase in cervical mucus as well as decrease of the endometrial lining. Both IUDs cause inflammatory responses inside the uterus, which do not allow sperm to move easily through the uterus and up into the fallopian tubes to unite with an egg.

Continue Learning about IUD (Intrauterine Device)

How do copper IUDs work?
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Copper IUDs (intrauterine devices) work in two ways. The copper in the IUD makes it difficult for sp...
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You can have ParaGard (T 380A Intrauterine Copper Contraceptive) removed from your uterus whenev...
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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.