What should you know about a copper evaporator coil?

In reproductive health, coil usually refers to an intrauterine device (IUD), not an appliance component. The copper device releases copper into the uterus. This interferes with sperm movement and fertilisation, and it does not rely on daily action or contain contraceptive hormones. A clinician checks whether it is suitable, discusses insertion, and places it through the cervix. It can be removed when you want to try for pregnancy, with fertility expected to return after removal. Learn more about the device in [Copper IUD Device](/materials/copper-iud-device/).

Cramping and light bleeding can occur after insertion. Periods may become heavier, longer, or more uncomfortable, particularly during the early adjustment period. The device does not protect against sexually transmitted infections, so condoms may still be needed for infection protection.

Before insertion, tell the clinician about possible pregnancy, unexplained bleeding, pelvic infection symptoms, allergies, medicines, and previous problems with an IUD. Afterward, follow the aftercare advice you receive and notice how pain and bleeding change. You may be shown how to feel for the two threads near the cervix; do not pull them. If the threads feel different or cannot be felt, arrange a check and use another contraceptive method until you receive advice. A hormonal option is described in [Hormonal Coil](/treatments/contraception-and-family-planning/hormonal-coil/).

Seek urgent medical help for severe or worsening lower-abdominal pain, fainting, heavy bleeding, fever, or unusual-smelling vaginal discharge after insertion. Contact a clinician promptly if you think you may be pregnant, the device or its threads seem to be coming out, or pain during sex continues. Sudden severe pain with a missed period needs urgent assessment because pregnancy with an IUD requires prompt review.

Ask which copper IUD is appropriate for you, what insertion discomfort and bleeding to expect, how to check the threads, when a review is needed, and which symptoms should prompt same-day care. You can also ask how it compares with a hormonal IUD if heavier periods are a concern.