An intrauterine device (IUD) is a form of birth control that a healthcare provider inserts into the uterus. There are two types of IUDs: copper IUDs and hormonal IUDs. Copper IUDs prevent pregnancy by not allowing sperm to fertilize the egg and may also make it harder for a fertilized egg to implant in the uterus. Hormonal IUDs work in a similar way, but also thicken the cervical mucus and thin the uterine lining, which prevents sperm from fertilizing the egg and implanting. Hormonal IUDs can also help reduce menstrual flow and cramps.

IUDs are the most commonly used type of long-acting reversible contraception (LARC). Once an IUD is inserted, you don’t have to worry about birth control until it’s time to replace it, which can be three to 10 years, depending on the brand. IUDs are very effective at preventing pregnancy, with fewer than 1 out of 100 typical couples using an IUD having an accidental pregnancy over the course of a year.

IUDs are a safe, effective, and convenient form of birth control. They are a good option for many people, but are not recommended for someone with pelvic inflammatory disease (PID) or an active STD infection, who is already pregnant or may be pregnant, or who has problems with her uterus.

In summary, an IUD is a form of birth control that a healthcare provider inserts into the uterus. It can prevent pregnancy for several years and is a safe, effective, and convenient form of birth control. Copper IUDs prevent pregnancy by not allowing sperm to fertilize the egg, while hormonal IUDs work in a similar way and can also help reduce menstrual flow and cramps.