IUD

abbreviation or noun

ˌī-(ˌ)yü-ˈdē 

plural IUDs

: a device inserted into and left in the uterus to prevent conception

specifically : a T-shaped device containing either progestin or copper that is inserted into and left in the uterus to prevent conception by blocking ovulation, thickening cervical mucus, or interfering with sperm motility

Once an IUD is inserted, you don't have to worry about birth control until it's time to replace it (three to 10 years, depending on the brand).

—Cleveland Clinic

… got relief by changing her birth control to a progestin-emitting IUD, which lightened her periods without dramatically adding extra hormones in the rest of her body.

—Laura Beil

If you don't want back-to-back pregnancies, contraception post-childbirth is key. You can go back on some types of birth control, like … hormonal or copper IUDs, immediately after giving birth.

—Anna Medaris

called also intrauterine contraceptive device, intrauterine device, IUCD

Examples of IUD in a Sentence

Recent Examples on the Web

Many women even took to the comments section to share their own pregnancy revelations despite having an IUD, leading to more than 6,400 comments on the post so far. — Alyce Collins, MSNBC Newsweek, 1 Sep. 2025

These can include aromatase inhibitors to suppress estrogen production, or progestins, which can be taken orally or administered via an intrauterine device (IUD). — Tabitha Britt, Flow Space, 29 Oct. 2025

Much of the current criticism around lack of attention to pain in OB-GYN procedures focuses on IUD insertions. — Maryl Sackeim, STAT, 20 Mar. 2026

Multiple studies have shown birth control use is not associated with infertility, and for people desiring an IUD, there are many effective options to help manage discomfort with the insertion. — Karen Greiner, San Diego Union-Tribune, 10 Mar. 2026

Word History

First Known Use

1964, in the meaning defined above

Kids Definition

IUD

noun

ˌī-ˌyü-ˈdē 

: intrauterine device

Medical Definition

IUD

abbreviation or noun

ˌī-ˌü-ˈdē 

: a device inserted into and left in the uterus to prevent conception

specifically : a T-shaped device containing either progestin or copper that is inserted into and left in the uterus to prevent conception by blocking ovulation, thickening cervical mucus, or interfering with sperm motility

called also intrauterine contraceptive device, intrauterine device, IUCD