Intrauterine Device | Contraceptive - Britannica

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intrauterine device contraceptive Ask Anything Homework Help Also known as: IUD Written by Kara Rogers Kara Rogers is the senior editor of biomedical sciences at Encyclopædia Britannica, where she oversees a range of content from medicine and genetics to microorganisms. She joined Britannica in 2006 and... Kara Rogers Fact-checked by Britannica Editors Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree.... Britannica Editors History Britannica AI Ask Anything Homework Help Table of Contents Table of Contents Ask Anything Top Questions

What is an intrauterine device (IUD)?

An intrauterine device (IUD) is a small, T-shaped device that is inserted into the uterus to provide long-acting, reversible contraception.

What are the two main types of IUDs?

The two main types of IUDs are hormonal and copper, which differ in the mechanisms by which they act to prevent fertilization.

How do hormonal IUDs work?

Hormonal IUDs work by releasing a synthetic hormone (progestin) that thickens cervical mucus, thins the uterine lining, and sometimes suppresses ovulation.

How do copper IUDs prevent pregnancy?

Copper IUDs prevent pregnancy by releasing copper ions that impair the viability of sperm.

What are some side effects of IUDs?

Hormonal IUDs may cause lighter periods, whereas copper IUDs may cause heavier periods. Both types also carry complications of expulsion, infection, allergic and inflammatory reactions, and, rarely, uterine perforation.

intrauterine device (IUD), small, T-shaped device inserted into the uterus to provide long-acting, reversible contraception (LARC). Intrauterine devices (IUDs) are reliable and remove risks of user error, such as forgetting to take a daily pill. They are one of the most effective forms of birth control available, preventing pregnancy in 99 percent of instances.

There are two main types of IUDs, hormonal and copper, both of which prevent fertilization of the egg. Hormonal IUDs do so by continuously releasing a synthetic hormone (progestin) that thickens cervical mucus to prevent sperm from reaching the egg and thins the uterine lining; some hormonal IUDs suppress ovulation. Copper IUDs work through the release of copper ions, which impair the viability of sperm. Protection begins immediately after insertion for copper IUDs and within about a week for most hormonal IUDs; some hormonal IUDs inserted within seven days of menstruation may provide immediate protection. Depending on the specific product, a hormonal IUD can provide protection for three to eight years, while some copper IUDs can last as long as 10 years. They can be removed at any time, after which fertility usually returns quickly.

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IUDs are associated with various side effects. For example, hormonal IUDs typically result in lighter, less painful periods, or even no period at all, and for this reason they are sometimes used to help manage such conditions as heavy and painful periods, endometriosis, polycystic ovarian syndrome (PCOS), and symptoms related to perimenopause. Copper IUDs may cause heavier and longer periods with more cramping, especially in the first few months after insertion. Some individuals experience hypersensitivity reactions to progestins released by hormonal IUDs or copper ions released by copper IUDs, and in some cases, other inflammatory and immune responses occur, which may be severe enough to prompt device removal. For both types of IUDs there is a risk of expulsion, in which the IUD slips out, as well as a risk of infection shortly after insertion. In rare cases uterine perforation, in which a tear forms in the wall of the uterus, occurs.

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